Storage battery pack and method of operating the same

ABSTRACT

A battery pack includes a secondary battery, a circuit having a consumer consuming power of the battery, terminals charging or discharging the pack, a switch that, when the voltage of the battery reaches the discharge cutoff voltage, is opened to stop discharge of the battery through the terminals, and a controller performing a first discharge operation activating the circuit and causing the consumer to consume a remaining power of the battery until a voltage of the battery reaches a first threshold value, higher than the discharge cutoff voltage, and stopping, when the voltage of the battery reaches the first threshold value, the first discharge operation. The controller also performs a second discharge operation activating the circuit and causing the consumer to consume the remaining power of the battery until the voltage of the battery reaches a third threshold value, lower than the discharge cutoff voltage.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 15/277,363, filed Sep. 27, 2016, which is a continuation ofPCT/JP2015/002679, filed May 27, 2015, which claims the foreign prioritybenefit of JP 2015-038811, filed Feb. 27, 2015, and JP 2014-143622,filed Jul. 11, 2014. The entire disclosures of the above-identifiedapplications are incorporated herein by reference in their entirety.

BACKGROUND 1. Technical Field

The present disclosure relates to a storage battery pack.

2. Description of the Related Art

A storage battery pack for supplying power to an electrical appliance ischarged by a charging device.

The following technique has been proposed: when abnormality occurs in abattery pack including a secondary battery, the battery pack, in whichabnormality occurs, is made unusable and internally connected to a dummyresistor so that the energy stored in the secondary battery is forced todischarge (see, for instance, Japanese Unexamined Patent ApplicationPublication No. 2010-251104). Also, the following technique has beenproposed: when abnormality occurs in a predetermined battery cell in anassembled battery in which secondary battery cells are connected inparallel, the battery cell is blocked from a charge/discharge circuitand is connected to a discharge circuit so that unnecessary capacity(electrical energy) of the battery cell is removed (see, for instance,Japanese Unexamined Patent Application Publication No. 2012-182890).

SUMMARY

However, in related art, safety has not been sufficiently studied.

One non-limiting and exemplary embodiment provides a storage batterypack that achieves improved safety compared with related art.

In one general aspect, the techniques disclosed here feature a storagebattery pack including: a secondary battery; and a circuit that includesa power consumer which consumes power of the secondary battery, and thatcauses the power consumer to consume a remaining power of the secondarybattery until a voltage of the secondary battery reaches a voltage lowerthan a discharge cutoff voltage.

A storage battery pack according to an aspect of the present disclosurehas improved safety compared to related art.

It should be noted that general or specific embodiments may beimplemented as a system, a method, an integrated circuit, a computerprogram, a storage medium such as a computer-readable CD-ROM, or anyselective combination thereof.

Additional benefits and advantages of the disclosed embodiments willbecome apparent from the specification and drawings. The benefits and/oradvantages may be individually obtained by the various embodiments andfeatures of the specification and drawings, which need not all beprovided in order to obtain one or more of such benefits and/oradvantages.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a storage battery pack separated from acharging device, according to a first embodiment;

FIG. 2 is a perspective view of a storage battery pack connected to acharging device, according to the first embodiment;

FIG. 3 is an outline view of a storage battery pack of another examplein the first embodiment;

FIG. 4 is a block diagram illustrating a system configuration of thestorage battery pack according to the first embodiment;

FIG. 5 is a diagram illustrating an operational flow of the storagebattery pack in the first example;

FIG. 6 is a flow chart illustrating an operation of the storage batterypack in the first example;

FIG. 7 is a block diagram illustrating a system configuration of astorage battery pack in a second example;

FIG. 8 is a diagram illustrating an operational flow of the storagebattery pack in the second example;

FIG. 9 is a flow chart illustrating an operation of the storage batterypack in the second example;

FIG. 10 is a diagram illustrating an operational flow of a storagebattery pack of a third example;

FIG. 11 is a flow chart illustrating an operation of the storage batterypack of the third example;

FIG. 12 is a diagram illustrating an operational flow of a storagebattery pack of a fourth example;

FIG. 13 is a flow chart illustrating an operation of the storage batterypack of the fourth example;

FIG. 14 is a diagram illustrating an operational flow of a storagebattery pack of a fifth example;

FIG. 15 is a flow chart illustrating an operation of the storage batterypack of the fifth example;

FIG. 16 is a diagram illustrating an operational flow of a storagebattery pack of a sixth example;

FIG. 17 is a flow chart illustrating an operation of the storage batterypack of the sixth example;

FIG. 18 is a perspective view of the storage battery pack in the secondembodiment;

FIG. 19 is a system configuration diagram of the storage battery pack inthe second embodiment;

FIG. 20 is a first diagram for explaining the basic operation of thestorage battery pack according to the second embodiment;

FIG. 21 is a second diagram for explaining the basic operation of thestorage battery pack according to the second embodiment;

FIG. 22 is a third diagram for explaining the basic operation of thestorage battery pack according to the second embodiment;

FIG. 23 is a graph for explaining first discharge and second dischargeof a secondary battery;

FIG. 24 is a flow chart for the first discharge and the seconddischarge;

FIG. 25 is a diagram for explaining a resistor for cell balance;

FIG. 26 is a perspective view illustrating an internal configuration ofthe storage battery pack according to the fifth embodiment;

FIG. 27 is a view illustrating the configuration of a heater accordingto the fifth embodiment;

FIG. 28 is a graph for explaining an operational example of the storagebattery pack according to the fifth embodiment; and

FIG. 29 is a perspective view of the storage battery pack including animage displayer.

DETAILED DESCRIPTION

In the above-mentioned storage battery pack in related art, it isdisclosed that when abnormality occurs, the remaining power of thesecondary battery is discharged. However, it has not been discussed towhat extent of the discharge is appropriate.

In a secondary battery, when the voltage reaches a nominal value(discharge cutoff voltage), a protection circuit is normally activatedand the discharge is stopped. When a secondary battery is dischargedwith a voltage lower than a discharge cutoff voltage, the performance ofthe second potential deteriorates, and thus, the secondary battery isprotected by activating a protection circuit. The protection circuitincludes a switching element, and when the protection circuit isactivated, the switching element is opened (turned OFF).

As a result of intensive study, the inventor has obtained the followingknowledge. Once a secondary battery is discharged until the voltagereaches a discharge cutoff voltage, even when the secondary battery isscrapped in a disposal process, the possibility of ignition and smokefrom the secondary battery is reduced. However, even when the secondarybattery is discharged until a discharge cutoff voltage is reached, theremaining capacity of the secondary battery is still left, and thus insome cases, a problem arises in that people who handles storage batterypacks may have electric shock or suffer burns due to heat generation ina disposal process.

Thus, a first aspect of the present disclosure provides a storagebattery pack including: a secondary battery; and a circuit that includesa power consumer which consumes power of the secondary battery, and thatcauses the power consumer to consume a remaining power of the secondarybattery until a voltage of the secondary battery reaches a voltage lowerthan a discharge cutoff voltage.

Consequently, in contrast to related art, the possibility of occurrenceof electric shock, burns of handlers of storage battery packs isreduced, and safety is improved.

Here, the above-mentioned voltage may be either one of the voltageitself and a physical quantity correlated with the voltage. Examples ofa physical quantity correlated with the voltage include the capacity ofthe secondary battery, and the output current of the secondary battery.

A second aspect of the present disclosure may be the storage batterypack in the first aspect, further including a switching element that,when the voltage of the secondary battery reaches the discharge cutoffvoltage, is opened to stop discharge of the secondary battery. Thecircuit does not include the switching element.

Consequently, even when the secondary battery has a lower voltage than adischarge cutoff voltage, the power of the secondary battery may beconsumed by the power consumer.

A third aspect of the present disclosure may be the storage battery packin the first aspect, further including a switching element that, whenthe voltage of the secondary battery reaches the discharge cutoffvoltage, stops discharge of the secondary battery. The circuit branchesfrom a circuit including the switching element, in an electric lineupstream of the switching element with respect to the secondary battery.

Consequently, even when the secondary battery has a lower voltage than adischarge cutoff voltage, the power of the secondary battery may beconsumed by the power consumer.

A fourth aspect of the present disclosure may be the storage batterypack in any one of the first to third aspects, further including areceiver that receives a command for activating the circuit from anexternal entity. When the receiver receives the command, the circuitcauses the power consumer to consume the remaining power of thesecondary battery.

Consequently, a command from an external entity allows to reduce thepossibility of occurrence of electric shock, burns of handlers ofstorage battery packs. In addition, for instance, even at the occurrenceof abnormality of the storage battery pack, when the command is executedby an external entity, consumption (hereinafter may be referred to asremaining power consumption) of the remaining power of the secondarybattery is made by the power consumer, and when the command is notexecuted, the remaining power consumption is not made. That is, forinstance, when abnormality occurs in the storage battery pack, theabove-mentioned remaining power consumption is made appropriately asneeded. In other words, for instance, when abnormality occurs in thestorage battery pack, it is possible to reduce the possibility of makingremaining power consumption although the consumption is unnecessary.

Here, the external entity may be in any form as long as a command foractivating the circuit is executable via the external entity, andincludes, for instance, users of storage battery packs, a collectioncontractor for storage battery packs, a server system, and aninformation terminal.

A fifth aspect of the present disclosure may be the storage battery packin the fourth aspect, further including a controller that, when thereceiver receives the command from the external entity, activates thecircuit and causes the power consumer to consume the remaining power ofthe secondary battery.

Consequently, a command from an external entity allows to reduce thepossibility of occurrence of electric shock, burns of handlers ofstorage battery packs. In addition, for instance, even when abnormalityoccurs in the storage battery pack, the remaining power of the secondarybattery is consumed by the power consumer appropriately as needed.

A sixth aspect of the present disclosure may be the storage battery packin the fourth aspect, in which the receiver is a mechanical switch thatis operated by an operator, and when an operator operates the mechanicalswitch to activate the circuit, the circuit is activated and causes thepower consumer to consume the remaining power of the secondary battery.

Consequently, an operation of the mechanical switch by an operatorallows to reduce the possibility of occurrence of electric shock, burnsof handlers of storage battery packs. In addition, for instance, evenwhen abnormality occurs in the storage battery pack, the remaining powerof the secondary battery is consumed by the power consumer appropriatelyas needed.

A seventh aspect of the present disclosure may be the storage batterypack in the fifth aspect, in which the receiver is a switch that isoperated by an operator, and when an operator operates the switch toactivate the circuit, the controller activates the circuit and causesthe power consumer to consume the remaining power of the secondarybattery.

Consequently, an operation of the switch by an operator allows to reducethe possibility of occurrence of electric shock, burns of handlers. Inaddition, for instance, even when abnormality occurs in the storagebattery pack, the remaining power of the secondary battery is consumedby the power consumer appropriately as needed.

An eighth aspect of the present disclosure may be the storage batterypack in the fifth aspect, in which the receiver is a receiving unit thatreceives the command from an external entity via wireless communication,and the controller, upon receiving the command via the receiving unit,activates the circuit and causes the power consumer to consume theremaining power of the secondary battery.

Consequently, a command from an external entity via wirelesscommunication allows to reduce the possibility of occurrence of electricshock, burns of handlers of storage battery packs. In addition, forinstance, even when abnormality occurs in the storage battery pack, theremaining power of the secondary battery is consumed by the powerconsumer appropriately as needed.

A ninth aspect of the present disclosure may be the storage battery packin any one of the fourth to eighth aspects, further including a notifierthat, when the receiver receives the command from an external entity,notifies that the secondary battery is scheduled to be discarded.

When the command is issued by the receiver, the remaining power of thesecondary battery is consumed by the power consumer, and normally, thestorage battery pack is subsequently discarded.

Thus, in contrast to the case where it is notified that a storagebattery pack is scheduled to be discarded, for instance, due to anoccurrence of abnormality in the storage battery pack, when a user ofthe storage battery pack has an intention to discard the storage batterypack, it is notified that the storage battery pack is scheduled to bediscarded. In short, it is possible to reduce the occurrence of the casewhere it is notified that a storage battery pack is scheduled to bediscarded although a user of the storage battery pack has no intentionof discarding the storage battery pack.

A tenth aspect of the present disclosure may be the storage battery packin any one of the first to eighth aspects, further including a notifierthat, when consumption of the remaining power of the secondary batteryby the power consumer is completed, notifies that the secondary batteryis scheduled to be discarded.

When consumption of the remaining power of the secondary battery iscompleted by the power consumer, normally, the storage battery pack issubsequently discarded.

Consequently, this reduces the occurrence of a case where it is notifiedthat a storage battery pack is scheduled to be discarded although a userof the storage battery pack has no intention of discarding the storagebattery pack.

An eleventh aspect of the present disclosure may be the storage batterypack in any one of the fourth to eighth aspects, further including anotifier that, when the receiver receives a command from an externalentity, notifies an information terminal of information to promptcontact with a collection contractor of the secondary battery.

When the command is issued by the receiver, the remaining power of thesecondary battery is consumed by the power consumer, and normally, thestorage battery pack is subsequently discarded.

Consequently, in contrast to the case where a user is notified ofinformation to prompt contact with a collection contractor, forinstance, at the occurrence of abnormality in the storage battery pack,a mobile terminal is notified of the information when the storagebattery pack is more likely to be discarded. In short, it is possible toreduce the occurrence of the case where an information terminal isnotified of information to prompt contact with a collection contractoralthough a user of the storage battery pack has no intention ofdiscarding the storage battery pack.

A twelfth aspect of the present disclosure may be the storage batterypack in any one of the first to eighth aspects, further including anotifier that, when consumption of the remaining power of the secondarybattery by the power consumer is completed, notifies an informationterminal of information to prompt contact with a collection contractorof the secondary battery.

When consumption of the remaining power of the secondary battery iscompleted by the power consumer, normally, the storage battery pack issubsequently discarded.

Therefore, it is possible to reduce the occurrence of the case where aninformation terminal is notified of information to prompt contact with acollection contractor although a user of the storage battery pack has nointention of discarding the storage battery pack.

A thirteenth aspect of the present disclosure may be the storage batterypack in any one of the first to twelfth aspects, further including anotifier that notifies that the remaining power of the secondary batteryis being consumed by the power consumer.

Thus, it is possible to recognize that the remaining power of thestorage battery pack is consumed by the power consumer.

A fourteenth aspect of the present disclosure may be the storage batterypack in any one of the first to thirteenth aspects, further including anotifier that notifies that consumption of the remaining power of thesecondary battery by the power consumer is completed.

Thus, it is possible to recognize that consumption of the remainingpower of the secondary battery by the power consumer is completed.

A fifteenth aspect of the present disclosure may be the storage batterypack in any one of the first to third, tenth, twelfth to fourteenthaspects, further including a controller that, when the storage batterypack is abnormal, activates the circuit and causes the power consumer toconsume the remaining power of the secondary battery.

Thus, when the storage battery pack is abnormal, consumption of theremaining power of the secondary battery is automatically made by thepower consumer, and in contrast to related art, it is possible to reducethe possibility of occurrence of electric shock, burns of handlers ofstorage battery packs.

A sixteenth aspect of the present disclosure may be the storage batterypack in any one of the fifth, seventh, eighth, and fifteenth aspects, inwhich the controller deactivates the circuit in a state where a capacityis left that allows the controller to be operative, and completesconsumption of the remaining power of the secondary battery by the powerconsumer.

Thus, after the consumption of the remaining power of the secondarybattery by the power consumer is completed, an operation is operativevia the controller. The above-mentioned operation is set as needed andmay be an operation of transmitting a state information on the storagebattery pack to an external entity, for instance, via the communicatorprovided in the storage battery pack. Here, the state information on thestorage battery pack is information that indicates a state of thestorage battery pack, and examples thereof include, for instance, thevoltage, remaining capacity of the secondary battery, but the stateinformation is not limited to these examples. Also, examples of theexternal entity include a server system that holds the information onthe storage battery pack, and the information terminal of a user of thestorage battery pack.

A seventeenth aspect of the present disclosure may be the storagebattery pack in any one of the fifth, seventh, eighth, fifteenth, andsixteenth aspects, further including a communicator that allowscommunication with an external device. The controller, when completingconsumption of the remaining power of the secondary battery by the powerconsumer, transmits information indicating a remaining capacity of thesecondary battery to the external device via the communicator.

Thus, it is possible to recognize the remaining capacity of thesecondary battery when consumption of the remaining power of thesecondary battery by the power consumer is completed. Therefore, it ispossible to recognize whether or not consumption of the remaining powerof the secondary battery has been made reliably.

Here, the information indicating the remaining capacity of the secondarybattery may be either one of the remaining capacity itself and aphysical quantity correlated with the remaining capacity. Examples of aphysical quantity correlated with the remaining capacity include thevoltage, output current of the secondary battery.

An eighteenth aspect of the present disclosure may be the storagebattery pack in any one of the fifth, seventh, eighth, fifteenth, andsixteenth aspects, further including a communicator that allowscommunication with an external device. The controller, after completingconsumption of the remaining power of the secondary battery by the powerconsumer, transmits information indicating a remaining capacity of thesecondary battery to the external device via the communicator.

Thus, it is possible to recognize the remaining capacity of thesecondary battery when consumption of the remaining power of thesecondary battery by the power consumer is completed. Therefore, it ispossible to recognize whether or not consumption of the remaining powerof the secondary battery has been made reliably.

Here, the information indicating the remaining capacity of the secondarybattery may be either one of the remaining capacity itself and aphysical quantity correlated with the remaining capacity. Examples of aphysical quantity correlated with the remaining capacity include thevoltage, output current of the secondary battery.

A nineteenth aspect of the present disclosure may be the storage batterypack in any one of the fifth, seventh, eighth, and fifteenth aspects, inwhich the secondary battery includes a plurality of cells, and thecontroller deactivates the circuit before voltages of all the cellsreach 0 V, and completes consumption of the remaining power of thesecondary battery by the power consumer.

When the secondary battery includes cells, it is preferable that thecells have an uniform state of health (SOH). However, the cells exhibitdifferent SOHs as the storage battery pack is used more often. It is tobe noted that SOH is an index that indicates a degree of deteriorationof the secondary battery, and is, for instance, a ratio of the currentfull charge capacity with respect to the full charge capacity of thesecondary battery when not in use. Here, when the remaining power of thesecondary battery is consumed, the voltages of the cells are varied, andin some cells, the remaining capacities reach 0, i.e., the voltagesreach 0 V relatively early. When those cells with the reached 0 V arefurther discharged, polarity inversion occurs, and there arises aproblem in safety.

Thus, consumption of the power of the secondary battery by the powerconsumer is terminated before the voltages of all cells reaches 0 V, andthe number of cells in which polarity inversion occurs is therebyreduced compared with the case where the secondary battery is dischargeduntil the voltages of all cells reaches 0 V, and thus safety isimproved.

A twentieth aspect of the present disclosure may be the storage batterypack in the nineteenth aspect, in which when a voltage of at least oneof the cells reaches 0 V, the controller deactivates the circuit.

Thus, the number of cells, in which polarity inversion occurs due to theconsumption of the remaining power of the secondary battery, is reduced,and thus safety is improved.

A 21st aspect of the present disclosure may be the storage battery packin any one of the fifth, seventh, eighth, and fifteenth to twentiethaspects, further including a connector that is connected to anelectrical appliance in a freely detachable manner. The controllercauses not only the power consumer but also the electrical appliance toconsume the remaining power of the secondary battery via the connectoruntil a voltage of the secondary battery reaches a discharge cutoffvoltage.

Thus, it is possible to consume the remaining power of the secondarybattery more quickly.

A 22nd aspect of the present disclosure may be the storage battery packin any one of the fifth, seventh, eighth, and fifteenth to twentiethaspects, further including a connector that is connected to a chargingdevice to charge the secondary battery in a freely detachable manner.Upon detecting start of charge of the secondary battery in a state wherethe connector is connected to the charging device, the controller causesthe power consumer to consume the remaining power of the secondarybattery until a value indicating a remaining capacity of the secondarybattery reaches a threshold value or less for determining whether or notcontinuous use of the secondary battery is allowed.

In this manner, the above-mentioned discharge is performed at the timecharge, and a user does not have to discharge the secondary batteryseparately to determine whether or not continuous use is allowed. Also,since the secondary battery is discharged at the time of charge when theamount of stored power is estimated to be low, the time taken for thedischarge may be reduced.

Since the secondary battery is discharged at the appropriate timing asdescribed above, the time, in which the storage battery pack isavailable to a user for power supply to an electrical appliance, islikely to be secured, and thus the convenience of the storage batterypack is improved.

Here, the value indicating the remaining capacity of the secondarybattery may be either one of the remaining capacity itself and aphysical quantity correlated with the remaining capacity. Examples of aphysical quantity correlated with the remaining capacity include thevoltage of the secondary battery, the output current of the secondarybattery.

A 23rd aspect of the present disclosure may be the storage battery packin any one of the first to 22nd aspects, in which the secondary batteryincludes a plurality of cells, and the power consumer includes aresistor for cell balance for adjusting a voltage between the cells.

Like this, a resistor for cell balance may be used for discharge of thesecondary battery.

A 24th aspect of the present disclosure may be the storage battery packin any one of the first to 23rd aspects, in which the power consumer isa heating element that generates heat by consuming power discharged bythe secondary battery.

Thus, it is possible to heat the storage battery pack using the powerconsumer.

A 25th aspect of the present disclosure may be the storage battery packin the 24th aspect, in which the heating element surrounds a peripheryof the secondary battery.

Thus, it is possible to heat the periphery of the secondary batteryusing the power consumer.

A 26th aspect of the present disclosure may be the storage battery packin the 24th or 25th aspect, in which upon decrease of a temperatureinside the storage battery pack, the controller activates the circuitand heats the secondary battery by the power consumer.

Thus, reduction of the temperature of the storage battery pack islessened, and the occurrence frequency of an operational failure due toa low temperature of the secondary battery is reduced.

A 27th aspect of the present disclosure may be the storage battery packin the 22nd aspect, in which the controller performs the discharge whenthe value indicating the remaining capacity of the secondary battery isgreater than the first threshold value and less than or equal to asecond threshold value which is less than a value indicating fullcharge.

Thus, since the above-mentioned discharge is performed when theremaining capacity of the secondary battery is less than the full chargecapacity, the secondary battery may be discharged in a shorter timecompared with the case where the above-mentioned discharge is performedat the time of full charge.

A 28th aspect of the present disclosure may be the storage battery packin the 22nd aspect, further including a storage that stores a history ofthe discharge, and in the storage battery pack, the controller performssubsequent discharge after lapse of a predetermined period.

Thus, discharge of the secondary battery is performed not for everycharge of the secondary battery but performed under a necessarycondition for elapse of a predetermined period. Therefore, unnecessarydischarge may be reduced in a situation where the time interval betweencharges is short and a variation of the battery life is estimated to below depending on setting of a predetermined period. Furthermore, it ispossible to suppress deterioration (reduction in the life) of thesecondary battery by reducing the number of times of discharge. Thepredetermined period is set to be longer than the time interval in whichcharge is performed.

A 29th aspect of the present disclosure may be the storage battery packin any one of the 22nd, 27th and 28th aspects, in which the controllerfurther determines whether or not continuous use of the secondarybattery is allowed, based on the amount of discharge of the secondarybattery, the discharge causing the value indicating the remainingcapacity of the secondary battery to change from the value indicatingfull charge to the first threshold value or less.

A 30th aspect of the present disclosure may be the storage battery packin any one of the 22nd, 27th and 28th aspects, further including acommunicator that communicates with an external device, and thecommunicator transmits to the external device an amount of dischargecausing the value indicating the remaining capacity of the secondarybattery to change from the value indicating full charge to the firstthreshold value or less, and receives from the external deviceinformation indicating whether or not continuous use of the secondarybattery is allowed.

Like this, whether or not continuous use of the secondary battery afterdischarge is allowed may be determined by the storage battery pack, ormay be determined by an external device (for instance, a chargingdevice, a server system, an information terminal).

A 31st aspect of the present disclosure may be the storage battery packin any one of the 22nd, 27th to 30th aspects, further including adisplayer that displays at least one of information indicating thedischarge is in operation and information indicating whether or notcontinuous use of the secondary battery is allowed.

This makes it possible to check a state of the secondary battery by thestorage battery pack alone.

A 32nd aspect of the present disclosure may be the storage battery packin any one of the 22nd, 27th and 28th aspects, further including acommunicator that communicates with an external device, and thecontroller transmits at least one of information indicating thedischarge is in operation and information indicating whether or notcontinuous use of the secondary battery is allowed to the externaldevice via the communicator.

This allows recognition of a state of the secondary battery via theexternal device. Here, examples of the external device include acharging device, a server system, and an information terminal.

A 33rd aspect of the present disclosure may be the storage battery packin any one of the 22nd, 27th to 32nd aspects, in which when it isdetermined that continuous use of the secondary battery is not allowed,the controller discharges the secondary battery using the power consumeruntil the value indicating the remaining capacity of the secondarybattery falls below a third threshold value which is less than the firstthreshold value.

In this manner, the secondary battery, for which it is determined thatcontinuous use is not allowed, is further discharged, thereby making itpossible to reduce the dangerous possibility such as ignition, smoke.Therefore, it is possible to improve the safety in discarding thestorage battery pack.

Here, the third threshold value may be a value that indicates theremaining capacity of the secondary battery when the voltage is lowerthan a discharge cutoff voltage.

After the discharge, it is possible to reduce the possibility ofoccurrence of electric shock, burns of handlers of storage batterypacks.

A 34th aspect of the present disclosure may be the storage battery packin any one of the 22nd, 27th to 33rd aspects, further including anabnormality detector that detects abnormality of the storage batterypack, and when the abnormality detector detects abnormality of thestorage battery pack, the controller discharges the secondary batteryusing the power consumer until the value indicating the remainingcapacity of the secondary battery falls below a third threshold valuewhich is less than the first threshold value.

Thus, when abnormality of the storage battery pack is detected, thesecondary battery is further discharged, thereby making it possible toreduce the dangerous possibility such as ignition, smoke. Therefore, itis possible to improve the safety in discarding the storage battery packin which abnormality is detected.

A 35th aspect of the present disclosure may be the storage battery packin the 34th aspect, further including a displayer that upon detection ofabnormality of the storage battery pack by the abnormality detector,displays information indicating the abnormality.

Thus, when abnormality occurs in the secondary battery, the storagebattery pack alone is able to notify an external entity of theabnormality.

A 36th aspect of the present disclosure may be the storage battery packin the 34th aspect, further including a communicator that communicateswith a charging device, and when the abnormality detector detectsabnormality of the storage battery pack, the controller transmitsinformation indicating the abnormality to the charging device via thecommunicator.

Thus, it is possible to detect an occurrence of abnormality of thestorage battery pack on the charging device side.

A 37th aspect of the present disclosure may be the storage battery packin any one of the 22nd, 27th to 36th aspects, further including acurrent measure that measures a current which flows from the secondarybattery to an electrical appliance connected to the connector, and acurrent which flows from the secondary battery to the power consumer,and the current measure is provided between the secondary battery andthe power consumer.

Thus, it is possible to check a current value of the secondary batterywhen it is discharged, using the power consumer.

Here, the above-mentioned electrical appliance is, for instance, acharging device that charges the storage battery pack. The remainingpower of the secondary battery may be consumed by a load in the chargingdevice.

A 38th aspect of the present disclosure may be the storage battery packin the 22nd aspect, in which the controller causes not only the powerconsumer but also the electrical appliance connected to the connector toconsume the power of the secondary battery.

Thus, it is possible to determine more quickly whether or not continuoususe of the secondary battery is allowed.

Here, the above-mentioned electrical appliance is, for instance, acharging device that charges the storage battery pack. The remainingpower of the secondary battery may be consumed by a load in the chargingdevice.

A 39th aspect of the present disclosure may be the storage battery packin any one of the fifth, seventh, fifteenth to 38th aspects, furtherincluding a switcher that switches between presence and absence ofelectrical connection of the secondary battery and the power consumer,and the controller performs the discharge by controlling the switcher toelectrically connect the secondary battery and the power consumer.

Like this, specifically, the above-mentioned discharge is performed, forinstance, based on the control of a switcher.

In addition, a 40th aspect of the present disclosure provides a methodof operating a storage battery pack, the method including: a step (a) ofactivating a circuit including the power consumer; and a step (b) ofthen consuming the remaining power of the secondary battery by the powerconsumer in the activated circuit until the voltage of the secondarybattery reaches a voltage lower than a discharge cutoff voltage.

Consequently, in contrast to related art, the possibility of occurrenceof electric shock, burns of handlers of storage battery packs isreduced, and safety is improved.

A 41st aspect of the present disclosure provides the method of operatinga storage battery pack in the 40th aspect, the storage battery packincluding a switching element that is opened to stop discharge of thesecondary battery when the voltage of the secondary battery reaches thedischarge cutoff voltage, the circuit not including the switchingelement.

Consequently, even when the secondary battery has a lower voltage thanthe discharge cutoff voltage, the power of the secondary battery may beconsumed by the power consumer.

A 42nd aspect of the present disclosure provides the method of operatinga storage battery pack in the 40th aspect, the storage battery packincluding a switching element that stops discharge of the secondarybattery when the voltage of the secondary battery reaches the dischargecutoff voltage. The circuit branches from a circuit including theswitching element, in an electric line upstream of the switching elementwith respect to the secondary battery.

Consequently, even when the secondary battery has a lower voltage than adischarge cutoff voltage, the power of the secondary battery may beconsumed by the power consumer.

A 43rd aspect of the present disclosure may be the method of operating astorage battery pack in the 40th aspect, including a step (c) ofreceiving a command from an external entity to activate the circuit, andwhen the command is received, the step (a) is performed.

Consequently, a command from an external entity allows to reduce thepossibility of occurrence of electric shock, burns of handlers ofstorage battery packs. In addition, for instance, even at the occurrenceof abnormality of the storage battery pack, when the command is executedby an external entity, consumption (hereinafter may be referred to asremaining power consumption) of the remaining power of the secondarybattery is made by the power consumer, and when the command is notexecuted, the remaining power consumption is not made. That is, forinstance, when abnormality occurs in the storage battery pack, theabove-mentioned remaining power consumption is made appropriately asneeded. In other words, for instance, when abnormality occurs in thestorage battery pack, it is possible to reduce the possibility of makingremaining power consumption although the consumption is unnecessary.

A 44th aspect of the present disclosure may be the method of operating astorage battery pack in the 43rd aspect, in which when the command isreceived, the controller activates the circuit and causes the circuit toconsume the remaining power of the secondary battery in the step (a).

Consequently, a command from an external entity allows to reduce thepossibility of occurrence of electric shock, burns of handlers ofstorage battery packs. In addition, for instance, even when abnormalityoccurs in the storage battery pack, the remaining power of the secondarybattery is consumed by the power consumer appropriately as needed.

A 45th aspect of the present disclosure may be the method of operating astorage battery pack in the 43rd aspect, in which the step (c) is a stepof receiving an operation to activate the circuit by an operator for amechanical switch provided in the storage battery pack.

Consequently, an operation of the mechanical switch by an operatorallows to reduce the possibility of occurrence of electric shock, burnsof handlers of storage battery packs. In addition, for instance, evenwhen abnormality occurs in the storage battery pack, the remaining powerof the secondary battery is consumed by the power consumer appropriatelyas needed.

A 46th aspect of the present disclosure may be the method of operating astorage battery pack in the 44th aspect, in which the step (c) is a stepof receiving an operation to activate the circuit by an operator for aswitch provided in the storage battery pack.

Consequently, an operation of the switch by an operator allows to reducethe possibility of occurrence of electric shock, burns of handlers ofstorage battery packs. In addition, for instance, even when abnormalityoccurs in the storage battery pack, the remaining power of the secondarybattery is consumed by the power consumer appropriately as needed.

A 47th aspect of the present disclosure may be the method of operating astorage battery pack in the 44th aspect, in which the step (c) is a stepof receiving the command from an external entity via wirelesscommunication.

Consequently, a command from an external entity via wirelesscommunication allows to reduce the possibility of occurrence of electricshock, burns of handlers of storage battery packs. In addition, forinstance, even when abnormality occurs in the storage battery pack, theremaining power of the secondary battery is consumed by the powerconsumer appropriately as needed.

A 48th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 43rd to 47th aspects, furtherincluding a step (d3) of, upon receiving the command from an externalentity by the receiver, notifying that the secondary battery isscheduled to be discarded.

When the command is issued, the remaining power of the secondary batteryis consumed by the power consumer, and normally, the storage batterypack is subsequently discarded.

Thus, in contrast to the case where it is notified that a storagebattery pack is scheduled to be discarded, for instance, due to anoccurrence of abnormality in the storage battery pack, when a user ofthe storage battery pack has an intention to discard the storage batterypack, it is notified that the storage battery pack is scheduled to bediscarded. In short, for instance, when abnormality occurs in thestorage battery pack, it is possible to reduce the occurrence of thecase where it is notified that a storage battery pack is scheduled to bediscarded although a user of the storage battery pack has no intentionof discarding the storage battery pack.

A 49th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 40th to 47th aspects, furtherincluding a step (d4) of, upon completion of the consumption of thepower of the secondary battery by the power consumer, notifying that thesecondary battery is scheduled to be discarded.

When consumption of the remaining power of the secondary battery is madeby the power consumer, normally, the storage battery pack issubsequently discarded.

Consequently, this reduces the occurrence of a case where it is notifiedthat a storage battery pack is scheduled to be discarded although a userof the storage battery pack has no intention of discarding the storagebattery pack.

A 50th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 43rd to 47th aspects, furtherincluding a step (d5) of, upon receiving a command by the receiver froman external entity, notifying an information terminal of information toprompt contact with a collection contractor of the secondary battery.

When the command is issued, the remaining power of the secondary batteryis consumed by the power consumer, and normally, the storage batterypack is subsequently discarded.

Consequently, in contrast to the case where a user is notified ofinformation to prompt contact with a collection contractor, forinstance, at the occurrence of abnormality in the storage battery pack,an information terminal is notified of the information when the storagebattery pack is more likely to be discarded. In short, it is possible toreduce the occurrence of the case where an information terminal isnotified of information to prompt contact with a collection contractoralthough a user of the storage battery pack has no intention ofdiscarding the storage battery pack.

A 51st aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 40th to 47th aspects, furtherincluding a step (d6) of, upon completion of the consumption of thepower of the secondary battery by the power consumer, notifying aninformation terminal of information to prompt contact with a collectioncontractor of the secondary battery.

When consumption of the remaining power of the secondary battery is madeby the power consumer, normally, the storage battery pack issubsequently discarded.

Therefore, it is possible to reduce the occurrence of the case where aninformation terminal is notified of information to prompt contact with acollection contractor although a user of the storage battery pack has nointention of discarding the storage battery pack.

A 52nd aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 40th to 51st aspects, furtherincluding a step (d1) of notifying that the remaining power of thesecondary battery is being consumed by the power consumer.

Thus, it is possible to recognize that the remaining power of thestorage battery pack is consumed by the power consumer.

A 53rd aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 40th to 52nd aspects, furtherincluding a step (d2) of notifying that consumption of the remainingpower of the secondary battery by the power consumer is completed.

Thus, it is possible to recognize that consumption of the remainingpower of the secondary battery by the power consumer is completed.

A 54th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 40th, 49th, 51st to 53rd aspects,in which when the storage battery pack is abnormal, the step (a) isperformed.

Thus, when the storage battery pack is abnormal, consumption of theremaining power of the secondary battery is made by the power consumer,and in contrast to related art, it is possible to reduce the possibilityof occurrence of electric shock, burns of handlers of storage batterypacks.

A 55th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 44th, 46th, 47th, and 54thaspects, further including a step (e) of terminating the consumption ofthe remaining power of the secondary battery by the power consumer in astate where a capacity is left that allows the secondary battery itselfto be operative.

Thus, even after the consumption of the remaining power of the secondarybattery by the power consumer is completed, the storage battery pack isoperative. The above-mentioned operation is set as needed and may be anoperation of transmitting a state information on the storage batterypack to an external entity, for instance, via the communicator providedin the storage battery pack. Here, the state information on the storagebattery pack is information that indicates a state of the storagebattery pack, and examples thereof include, for instance, the voltage,remaining capacity of the secondary battery, but the state informationis not limited to these. Also, examples of the external entity include aserver system that holds the information on the storage battery pack,and the information terminal of a user of the storage battery pack.

A 56th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 44th, 46th, 47th, 54th and 55thaspects, further including a step (f1) of, upon completion ofconsumption of the remaining power of the secondary battery by the powerconsumer, transmitting information indicating the remaining capacity ofthe secondary battery to an external device via the communicatorprovided in the storage battery pack.

Thus, it is possible to recognize the remaining capacity of thesecondary battery when the consumption of the remaining power of thesecondary battery by the power consumer is completed. Therefore, it ispossible to recognize whether or not consumption of the remaining powerof the secondary battery has been made reliably.

A 57th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 44th, 46th, 47th, 54th and 55thaspects, further including a step (f2) of, after completion ofconsumption of the remaining power of the secondary battery by the powerconsumer, transmitting information indicating the remaining capacity ofthe secondary battery to an external device via the communicatorprovided in the storage battery pack.

Thus, it is possible to recognize the remaining capacity of thesecondary battery after the consumption of the remaining power of thesecondary battery by the power consumer is completed. Therefore, it ispossible to recognize whether or not consumption of the remaining powerof the secondary battery has been made reliably.

A 58th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 44th, 46th, 47th, and 54thaspects, further including a step (g) of terminating the consumption ofthe remaining power of the secondary battery including cells by thepower consumer before the voltages of all the cells reach 0 V.

When the secondary battery includes cells, it is preferable that thecells have an uniform degree of deterioration (SOH). However, the cellsexhibit different degrees of deterioration as the storage battery packis used more often. Here, when the remaining power of the secondarybattery is consumed, the voltages of the cells are varied, and in somecells, the voltages reach 0 V relatively early. When those cells withthe reached 0 V are further discharged, polarity inversion occurs, andthere arises a problem in safety.

Thus, consumption of the power of the secondary battery by the powerconsumer is terminated before the voltages of all cells reaches 0 V, andthe number of cells in which polarity inversion occurs is therebyreduced compared with the case where the secondary battery is dischargeduntil the voltages of all cells reaches 0 V, and thus safety isimproved.

A 59th aspect of the present disclosure may be the method of operating astorage battery pack in the 58th aspect, in which in the step (g), whenthe voltage of at least one of the cells reaches 0 V, the consumption ofthe remaining power of the secondary battery by the power consumer iscompleted.

Thus, the number of cells, in which polarity inversion occurs due to theconsumption of the remaining power of the secondary battery, is reduced,and thus safety is improved.

A 60th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 44th, 46th, 47th, and 54th to59th aspects, in which the stored power is supplied to the electricalappliance via a connector that electrically connects the storage batterypack and the electrical appliance until the voltage of the secondarybattery reaches a discharge cutoff voltage in the step (b), therebycausing not only the power consumer but also the electrical appliance toconsume the remaining power of the secondary battery.

A 61st aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 44th, 46th, 47th, and 54th to59th aspects, further including a step (h), upon detecting the start ofcharge of the secondary battery in a state where a connector isconnected to a charging device, the connector being connected to thecharging device in a freely detachable manner to charge the secondarybattery, discharging the secondary battery using the power consumeruntil the value indicating the remaining capacity of the secondarybattery reaches the first threshold value or less for determiningwhether or not continuous use of the secondary battery is allowed.

In this manner, the above-mentioned discharge is performed at the timecharge, and a user does not have to discharge the secondary batteryseparately to determine whether or not continuous use is allowed. Also,since the secondary battery is discharged at the time of charge when theamount of stored power is estimated to be low, the time taken for thedischarge may be reduced.

Since the secondary battery is discharged at the appropriate timing asdescribed above, the time, in which the storage battery pack isavailable to a user for power supply to an appliance, is secured, andthus the convenience of the storage battery pack may be improved.

A 62nd aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 40th to 61st aspects, in whichthe secondary battery includes cells, and the power consumer includes aresistor for cell balance for adjusting the voltages between the cells.

Like this, a resistor for cell balance may be used for discharge of thesecondary battery.

A 63rd aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 40th to 62nd aspects, in whichthe power consumer is a heating element that generates heat by consumingthe power discharged by the secondary battery.

Thus, it is possible to heat the storage battery pack using the powerconsumer.

A 64th aspect of the present disclosure may be the method of operating astorage battery pack in the 63rd aspect, in which the heating elementsurrounds the periphery of the secondary battery.

Thus, it is possible to heat the periphery of the secondary batteryusing the power consumer.

A 65th aspect of the present disclosure may be the method of operating astorage battery pack in the 63rd or 64th aspect, further including astep (i) of, upon decrease of the temperature inside the storage batterypack, activating the circuit and heating the secondary battery by thepower consumer.

Thus, reduction of the temperature of the storage battery pack islessened, and the occurrence frequency of an operational failure due toa low temperature of the secondary battery is reduced.

A 66th aspect of the present disclosure may be the method of operating astorage battery pack in the 61st aspect, in which in the step (i), whenthe remaining capacity of the secondary battery is greater than thefirst threshold value and less than or equal to a second threshold valuewhich is less than a value indicating full charge, discharge isperformed.

Thus, since the above-mentioned discharge is performed when theremaining capacity of the secondary battery is less than the full chargecapacity, the secondary battery may be discharged in a shorter timecompared with the case where the above-mentioned discharge is performedat the time of full charge.

A 67th aspect of the present disclosure may be the method of operating astorage battery pack in the 61st aspect, further including a step (j) ofstoring a history of the discharge and a step (k) of performingsubsequent discharge after lapse of a predetermined period.

Thus, discharge of the secondary battery is performed not for everycharge of the secondary battery but performed under a necessarycondition for elapse of a predetermined period. Therefore, unnecessarydischarge may be reduced in a situation where the time interval betweencharges is short and a variation of the battery life is estimated to below. Furthermore, it is possible to suppress deterioration (reduction inthe life) of the secondary battery by reducing the number of times ofdischarge. The predetermined period is set to be longer than the timeinterval in which charge is performed.

A 68th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 61st, 66th and 67th aspects,further including a step (I) of determining whether or not continuoususe of the secondary battery is allowed, based on the amount ofdischarge of the secondary battery, the discharge causing the remainingcapacity of the secondary battery to change from the value indicatingfull charge to the first threshold value or less.

A 69th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 61st, 66th and 67th aspects,further including: a step (m) of transmitting via a communicatorprovided in the storage battery pack to the external device an amount ofdischarge causing the value indicating the remaining capacity of thesecondary battery to change from the value indicating full charge to thefirst threshold value or less; and a step (n) of receiving from theexternal device information indicating whether or not continuous use ofthe secondary battery is allowed.

Like this, whether or not continuous use of the secondary battery afterdischarge is allowed may be determined by the storage battery pack, ormay be determined by an external device (for instance, a chargingdevice, a server system, an information terminal).

A 70th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 61st, 46th to 69th aspects,further including a step (o) of displaying at least one of informationindicating the discharge is in operation and information indicatingwhether or not continuous use of the secondary battery is allowed.

This makes it possible to check a state of the secondary battery by thestorage battery pack alone.

A 71st aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 61st, 66th and 67th aspects,further including a step (p) of transmitting via a communicator providedin the storage battery pack to the external device at least one ofinformation indicating the discharge is in operation and informationindicating whether or not continuous use of the secondary battery isallowed.

This allows recognition of a state of the secondary battery via theexternal device. Here, examples of the external device include acharging device, a server system, and an information terminal.

A 72nd aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 61st, 66th and 71th aspects,further including a step (q) of, upon determination that continuous useof the secondary battery is not allowed, discharging the secondarybattery using the power consumer until the remaining capacity of thesecondary battery falls below a third threshold value which is less thanthe first threshold value.

In this manner, the secondary battery, for which it is determined thatcontinuous use is not allowed, is further discharged, thereby making itpossible to reduce the dangerous possibility such as ignition, smoke.Therefore, it is possible to improve the safety in discarding thestorage battery pack.

Here, the third threshold value may be a value that indicates theremaining capacity of the secondary battery when the voltage is lowerthan a discharge cutoff voltage.

After the discharge, it is possible to reduce the possibility ofoccurrence of electric shock, burns of handlers of storage batterypacks.

A 73rd aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 61st, 66th to 72nd aspects,further including a step (r) of, in an abnormal condition of the storagebattery pack, discharging the secondary battery using the power consumeruntil the value indicating the remaining capacity of the secondarybattery falls below a third threshold value which is less than the firstthreshold value.

Thus, when the storage battery pack is abnormal, the secondary batteryis further discharged, thereby making it possible to reduce thedangerous possibility such as ignition, smoke. Therefore, it is possibleto improve the safety in discarding the storage battery pack.

Here, the third threshold value may be a value that indicates theremaining capacity of the secondary battery when the voltage is lowerthan a discharge cutoff voltage.

After the discharge, it is possible to reduce the possibility ofoccurrence of electric shock, burns of handlers of storage batterypacks.

A 74th aspect of the present disclosure may be the method of operating astorage battery pack in the 73rd aspect, further including a step (s)of, in an abnormal condition of the storage battery pack, displayinginformation indicating the abnormality.

Thus, when abnormality occurs in the storage battery pack, the storagebattery pack alone is able to notify an external entity of abnormality.

A 75th aspect of the present disclosure may be the method of operating astorage battery pack in the 73rd aspect, further including a step (t)of, in an abnormal condition of the storage battery pack, transmittingvia a communicator provided in the storage battery pack to the chargingdevice the information indicating the abnormality.

Thus, it is possible to detect an occurrence of abnormality of thestorage battery pack on the charging device side.

A 76th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 61st, 66th to 75th aspects,further including: a step (u) of measuring a current which flows fromthe secondary battery to an electrical appliance connected to theconnector by a current measure provided between the secondary batteryand the power consumer; and a step (v) of measuring a current whichflows from the secondary battery to the power consumer by the currentmeasure.

Thus, it is possible to check a current value of the secondary batterywhen it is discharged, using the power consumer.

A 77th aspect of the present disclosure may be the method of operating astorage battery pack in the 61st aspect, in which not only the powerconsumer but also an electrical appliance connected to the connector iscaused to consume the remaining power of the secondary battery in thestep (h).

Thus, it is possible to determine more quickly whether or not continuoususe of the secondary battery is allowed.

A 78th aspect of the present disclosure may be the method of operating astorage battery pack in any one of the 44th, 46th, 54th to 77th aspects,in which the circuit is activated by switching between presence andabsence of electrical connection of the secondary battery and the powerconsumer to electrically connect the secondary battery and the powerconsumer.

In this manner, the discharge is performed by switching between presenceand absence of electrical connection of the secondary battery and thepower consumer.

Hereinafter, a storage battery pack according to an aspect of thepresent disclosure will be specifically described with reference to thedrawings.

It is to be noted that each of the embodiments described belowillustrates a specific example of the present disclosure. The numericalvalues, shapes, materials, components, arrangement positions andconnection configuration of the components, steps, and order of thesteps that are presented in the following embodiments are examples,which are not intended to limit the present disclosure. In the followingembodiments, the components thereof, which are not described in theindependent claim that defines the most generic concept of the presentdisclosure, are regarded as any components.

It is to be noted that each of the drawings is schematicallyillustrated, and is not necessarily illustrated accurately. In thedrawings, essentially the same components are labeled with the samesymbol, and a redundant description may be omitted or simplified.

First Embodiment

A storage battery pack according to a first embodiment will bedescribed.

[Entire Configuration]

The overall configuration of a storage battery pack 100 in the firstembodiment will be described. FIG. 1 and FIG. 2 are perspective views ofthe storage battery pack and a charging device according to the firstembodiment. FIG. 1 illustrates the storage battery pack 100 and thecharging device 200 which are separated from each other, and FIG. 2illustrates the storage battery pack 100 and the charging device 200which are connected to each other.

First, the storage battery pack 100 will be described. As illustrated inFIG. 1 and FIG. 2, the storage battery pack 100 includes a main body120, a connector 102, and a displayer 109.

The storage battery pack 100 is a storage battery pack connected to anelectrical appliance. For instance, the storage battery pack 100 isutilized as a power supply for electrical appliances, electric toolsused by electric mobile objects, consumers of electric power. Examplesof an electric mobile body include an electric assisted bicycle, anelectric motorcycle, an electric wheelchair, an electric vehicle, and ahybrid vehicle. Examples of electrical appliances used by consumers ofelectric power include an air conditioner, a lighting device, arefrigerator, a medical device, and an air-conditioning unit. Examplesof electric tools include an electric drill.

It is to be noted that the storage battery pack 100 may be a storagebattery pack exclusively for specific electrical appliances.

Also, the storage battery pack 100 may be used for electrical appliancesof different types. For instance, the storage battery pack 100 may beused for both electric assisted bicycles and lighting devices.

The main body 120 is the body of the substantially rectangularparallelepiped-shaped storage battery pack 100 including a secondarybattery and a control circuit for the secondary battery therein. Theupper surface of the main body 120 is provided with a holder 130 a userto hold the storage battery pack 100 and a receiver 114, and the lowersurface (bottom surface) of the main body 120 is provided with aconnector 102. In this example, the holder 130 is a handle for thestorage battery pack 100, but is for illustration only and is notlimited to this.

The receiver 114 receives from an external entity a command foractivating a circuit including a power consumer. The receiver 114 may bein any form as long as the receiver 114 is able to receive theabove-mentioned command. The receiver 114 may be, for instance, a switchor a communicator that receives the above-mentioned command via wirelesscommunication. The switch may be a mechanical switch such that whenturned on by an operator, the remaining power of the secondary batteryis consumed by the power consumer not via the controller, or may be aswitch such that when turned on, the remaining power of the secondarybattery is consumed via the controller. It is to be noted that thereceiver 114 may be configured to allow depression thereof only bypointed end such as a pin in order to avoid erroneous depressing by auser.

When the receiver 114 is a switch, the switch may be provided in thelower surface of the main body 120 as illustrated in FIG. 3. The switchas the receiver 114 may be covered by a seal 114 a as illustrated inFIG. 3. In this case, the switch is operated with the seal 114 aremoved.

Alternatively, the above-mentioned external entity may be a commandingperson or may be an external device. Examples of a commanding personinclude a user of the storage battery pack 100, and a collectioncontractor. Examples of an external device include an informationterminal, a server system. Examples of an information terminal include,for instance, a mobile phone such as a smartphone, a smart tablet, anotebook PC.

When the above-mentioned command is received by the receiver 114, theremaining power of the secondary battery is consumed by the powerconsumer. Consequently, a command from an external entity allows toreduce the possibility of occurrence of electric shock, burns ofhandlers of storage battery packs. In addition, for instance, even atthe occurrence of abnormality of the storage battery pack, when thecommand is executed by an external entity, consumption of the remainingpower of the secondary battery is made by the power consumer, and whenthe command is not executed, the remaining power consumption is notmade. That is, for instance, when abnormality occurs in the storagebattery pack, the above-mentioned remaining power consumption is madeappropriately as needed. In other words, for instance, when abnormalityoccurs in the storage battery pack, it is possible to reduce thepossibility of making remaining power consumption although theconsumption is unnecessary.

The connector 102 is mounted on an electrical appliance in a freelydetachable manner. Terminals for charging or discharging the storagebattery pack are provided in the connector 102. An electrical applianceconnected to the connector 102 may be an electrical appliance thatconsumes the power of the secondary battery 101 and operates, or may bethe charging device 200 that charges the secondary battery 101. When theconnector 102 is connected to a terminal section 202 of the chargingdevice 200, the terminals are electrically connected to an internalcircuit of the charging device 200. It is to be noted that the connector102 may be provided with a terminal for charge, a terminal fordischarge, and a terminal for communication (for control) separately.

The displayer 109 includes a remaining amount display button 109 a, aremaining amount displayer 109 b, and an abnormality displayer 109 c.

The remaining amount displayer 109 b is principally a displayer thatdisplays the remaining capacity of a secondary battery built in thestorage battery pack 100. Specifically, the remaining amount displayer109 b includes light emitting diodes (LED), and the remaining capacityof the secondary battery is displayed by the number of LEDs which arelit. In addition, the remaining amount displayer 109 b may also serve asa notifier that notifies of not only the remaining capacity of thesecondary battery, but also other states of the storage battery pack.For instance, when the remaining amount displayer 109 b is formed of alight emitter such as an LED, blinking of the light emitter may notifythat the remaining power of the secondary battery 101 is being consumedby the power consumer 105, the storage battery pack 100 is beingcharged, or the storage battery pack is abnormal. Also, those multiplestates may be distinguished and notified using at least one of theblinking rate of the light emitter and the number of blinking lightemitters.

The remaining amount display button 109 a is a button that is to bepressed by a user. When the remaining amount display button 109 a ispressed, a certain number of LEDs (the remaining amount displayer 109 b)in the remaining amount displayer 109 b according to the remainingcapacity of the secondary battery built in the storage battery pack 100is lit.

The abnormality displayer 109 c notifies an external entity ofinformation indicating abnormality of the storage battery pack 100.Thus, at the occurrence of abnormality of the storage battery pack 100,the storage battery pack 100 alone is able to notify a user of theabnormality. The abnormality displayer 109 c is formed of, for instance,an LED, but may be in any form as long as abnormality displayer 109 c isable to notify an external entity of abnormality. For instance,information such as a text information, an image information indicatingan occurrence of abnormality may be displayed on a display screen.

Next, the charging device 200 will be described. The charging device 200includes a main body 210, a terminal section 202, and a plug 201.

The charging device 200 is a charger for the storage battery pack 100.

The main body 210 is the main body of the charging device 200, thathouses an internal circuit and others of the charging device 200. Adepressed portion provided in the upper surface of the main body 210 isthe terminal section 202 to which the connector 102 of the storagebattery pack 100 is connected, and a lateral face of the main body 210is provided with the plug 201 via a power cable.

The terminal section 202 is a depressed portion having a shape and sizethat fit the connector 102, and the connector 102 is connected to thedepressed portion in a freely detachable manner (detachably). The bottomsurface of the terminal section 202 is provided with terminals thatcorrespond to the terminals of the connector 102. The terminal section202 and the connector 102 are connected, and thus each terminal in theterminal section 202 and each terminal provided in the connector 102 areconnected. Thus, the internal circuit of the storage battery pack 100and the internal circuit of the charging device 200 are electricallyconnected.

The plug 201 is an example of a power receiver, and is connected to apower supplier (for instance, an outlet) of an external power supply inorder to receive supply of power from the external power supply by thecharging device 200. Here, examples of an external power supply includea self-power generation type power supply such as a commercial system,or a solar cell system, a fuel cell system. It is to be noted that thecharging device 200 may receive supply of power from an external powersupply via a USB connector (USB socket) instead of the plug 201.

[System Configuration]

Next, the system configuration of the storage battery pack 100 will bedescribed. FIG. 4 is a block diagram illustrating the systemconfiguration of the storage battery pack 100 according to the firstembodiment.

As illustrated in FIG. 4, the storage battery pack 100 includes asecondary battery 101, a connector 102, a switch 103, a switch 104, apower consumer 105, a storage 106, a controller 107, a voltage detector108, a displayer 109, an abnormality detector 112 and a circuit 116.

The secondary battery 101 is formed by connecting electric cells (forinstance, a lithium-ion battery, a nickel hydride battery) in parallelor in series.

The connector 102 is connected to the terminal section 202 of thecharging device 200 in a freely detachable manner in order to charge thesecondary battery 101 as described above. Also, the connector 102 isconnectable (electrically and mechanically connectable) to an electricalappliance in a freely detachable manner.

The switch 103 a change switch (switcher) that switches ON and OFF ofelectrical connection, that is, presence and absence of electricalconnection between the secondary battery 101 and the power consumer 105based on the control of the controller 107. As the switch 103, forinstance, a MOSFET, a relay or the like is used. Also, when the receiver114 and the switch 103 are mechanical switches, ON and OFF of the switch104 are not switched by the control of the controller 107, but isdirectly switched by an operation of an operator on the receiver 114.

The switch 104 is a change switch (switcher) that switches between ONand OFF of electrical connection of the secondary battery 101 and theconnector 102 based on the control of the controller 107. As the switch104, for instance, a MOSFET or the like is used. When the voltage of thesecondary battery 101 reaches a standard value (discharge cutoffvoltage) at which discharge of the secondary battery 101 is stopped, theswitch 104 is opened by the control of controller 107. In other words,the switch 104 is an example of the switching element of the presentdisclosure.

The power consumer 105 is a load for causing the secondary battery 101to discharge. The power consumer 105 is, for instance, a resistor body,a heater, or a PTC thermistor.

The storage 106 holds the voltage value of the secondary battery 101.Also, the storage 106 may hold not only the voltage value of thesecondary battery 101, but also other state values indicating the stateof the secondary battery. Examples of the other state values of thesecondary battery include the remaining capacity of the secondarybattery, the output current of the secondary battery, the temperature ofthe secondary battery, and a degree of deterioration of the secondarybattery. As the degree of deterioration of the secondary battery, forinstance, the number of cycles of charge and discharge of the secondarybattery, the internal resistance of the secondary battery, or thelearning capacity of the secondary battery may be used. It is to benoted that the voltage value of the secondary battery, the outputcurrent value of the secondary battery may be included in the valueindicating the remaining capacity as a physical quantity correlated withthe remaining capacity.

The storage 106 may be any memory device, for instance, a semiconductormemory such as a flash memory.

The controller 107 controls the operation of the circuit 116. Thecontroller 107 may be a unit that has a control function, and includesan arithmetic processor (not illustrated) and a storage (notillustrated) that stores a control program. Examples of an arithmeticprocessor include an MPU and a CPU. Examples of a storage include amemory. The controller may be formed of a single controller thatperforms centralized control or formed of controllers that work in acooperative manner to perform distributed control. It is to be notedthat the storage 106 may also serves as the above-mentioned storage thatstores a control program.

Specifically, the controller 107 outputs a control signal to the switch103, thereby controlling ON and OFF of the switch 103. Thus, theoperation of the circuit 116 is turned ON or OFF, and power consumptionof the secondary battery 101 by the power consumer 105 can be turned ONor OFF. In addition, the controller 107 outputs a control signal to theswitch 104, thereby controlling ON and OFF of the switch 104. Thecontroller 107 is able to turn ON or OFF power supply of the secondarybattery 101 to an electrical appliance via the connector 102 by suchcontrol of the switch 104. Also, when the secondary battery 101 isconnected to the charging device 200 via the connector 102, the switch104 is turned ON or OFF, thereby allowing charge to the secondarybattery 101 to be ON or OFF. Also, the controller 107 fetches dataindicating the voltage value of the secondary battery 101 detected bythe voltage detector 108, and stores the data in the storage 106.Although the controller 107 is specifically a microcomputer, thecontroller 107 may be formed of a processor or a dedicated circuit.

The voltage detector 108 detects the voltage of the secondary battery101. The voltage detector 108 may detect, for instance, the voltageitself of the secondary battery 101 or may detect a physical quantitycorrelated with the voltage. Examples of a physical quantity correlatedwith the voltage include the remaining capacity of the secondary battery101, the output current of the secondary battery 101. Although thevoltage detector 108 is specifically a dedicated circuit (IC), thevoltage detector 108 may be achieved as a microcomputer or a processor.

The displayer 109 displays various states or operations of the secondarybattery 101 as described with reference to FIG. 1 and FIG. 2.

The abnormality detector 112 detects abnormality of the storage batterypack 100 and notifies the controller 107 of the abnormality. Theabnormality detector 112 may be in any form as long as it detectsabnormality of the storage battery pack 100. Specifically, theabnormality detector 112 is, for instance, a sensor that detects a statevalue of the secondary battery, an impact sensor, a submersion sensor,or a disassemble sensor. In the case where the abnormality detector 112is an impact sensor, the impact sensor is able to measure not only thepresence or absence of an impact received by the storage battery pack100, but also the magnitude and direction of the impact, and may be asensor that is able to record the history received impacts. Examples ofabnormality in the state value of the secondary battery include, forinstance, voltage abnormality, temperature abnormality, deteriorationdegree abnormality (battery life), and short-circuit abnormality of thesecondary battery. An example of voltage abnormality is abnormality inthe voltage balance of the cells included in the secondary battery 101.An example of temperature abnormality is the state where the temperatureof the secondary battery 101 reaches a threshold value or higher (hightemperature abnormality). An example of battery life is the state wherethe number of cycles of charge and discharge of the secondary battery101 reaches a threshold value or higher. An example of short-circuitabnormality is the state where the amount of voltage reduction of thesecondary battery 101 during no discharge of the secondary battery 101is a threshold value or higher. It is to be noted that when theabove-mentioned abnormality includes the voltage abnormality, thevoltage detector 108 is also used as the abnormality detector 112.

The circuit 116 is an electrical circuit including the power consumer105. Specifically, the circuit 116 includes the secondary battery 101,the switch 103, the power consumer 105, and an electrical conductor thatconnects these elements. The electrical conductor is, for instance, aconductive wire. As illustrated in FIG. 4, the circuit 116 branches froma circuit including the switch 104, in an electric line upstream of theswitch 104 with respect to the secondary battery 101. In other words,the circuit 116 does not include the switch 104 as a switching element.Thus, when the circuit 116 is activated, even when the voltage of thesecondary battery 101 is lower than a discharge cutoff voltage, theremaining power of the secondary battery 101 is consumed by the powerconsumer 105.

First Example

The operation of the storage battery pack 100 in the first example willbe described.

FIG. 5 is a diagram illustrating the operational flow of the storagebattery pack in the first example.

FIG. 6 is a flow chart illustrating the operation of the storage batterypack in the first example.

In the storage battery pack 100 in the present example, when abnormalityof the storage battery pack 100 is detected by the abnormality detector112 (S101), an external entity is notified of an occurrence of theabnormality via the displayer 109 c (S102). In the present example, asillustrated in FIG. 5(a), an LED serving as the abnormality displayer109 c is lit to notify of an occurrence of abnormality.

Here, when an operator performs ON operation for a switch serving as thereceiver 114 (S103), the switch 103 is closed (ON) by the controller107, and the circuit 116 is activated and the remaining power of thesecondary battery 101 is consumed by the power consumer 105 (S104). Inaddition, an external entity is notified that the remaining power of thesecondary battery 101 is being consumed (S105). Specifically, theconsumption of the remaining power of the secondary battery 101 in S104is made until the voltage of the secondary battery 101 falls below thedischarge cutoff voltage. Even though an electrical appliance isconnected to the connector of the storage battery pack 100, since theswitch 104 is opened (OFF) by the controller 107 due to an occurrence ofabnormality, the remaining power of the secondary battery 101 is notsupplied to the electrical appliance in S104. In S105, specifically, asillustrated in FIG. 5(b), a light emitter serving as the remainingamount displayer 109 b blinks, thereby notifying an external entity thatthe remaining power of the secondary battery 101 is being consumed.Examples of an operator include a user of the storage battery pack 100,a collection contractor who collects the storage battery pack 100, awaste disposal contractor who discards the collected storage batterypack 100.

When the switch 103 is opened (OFF) by the controller 107, and theoperation of the circuit 116 is stopped, the consumption of theremaining power of the secondary battery 101 by the power consumer 105is completed (S106). Also, an external entity is notified that theconsumption of the remaining power of the secondary battery 101 iscompleted (S107). In the present example, as illustrated in FIG. 5(c),the light emitter serving as the remaining amount displayer 109 b stopsblinking, thereby notifying an external entity that the consumption ofthe remaining power of the secondary battery 101 is completed.

Second Example

A storage battery pack 100 in a second example will be described.

FIG. 7 is a block diagram illustrating the system configuration of thestorage battery pack in the second example.

As illustrated in FIG. 7, the storage battery pack 100 of the presentexample includes a communicator 111. The communicator 111 performswireless communication with an external device such as an informationterminal, a server system. In the present example, the communicator 111is a communicator that performs short-distance wireless communicationsuch as Bluetooth (registered trademark), Zigbee (registered trademark),NFC, and Wi-Fi, and communicates with an information terminal. It is tobe noted that the communicator 111 may be a communicator that performswireless communication such as LTE which has a longer communicationdistance than short-distance wireless communication. The configurationexcept for this is the same as the system configuration of the storagebattery pack 100 in the first example illustrated in FIG. 4.

Next, the operation of the storage battery pack 100 in the presentexample will be described.

FIG. 8 is a diagram illustrating the operational flow of the storagebattery pack in the second example.

FIG. 9 is a flow chart illustrating the operation of the storage batterypack in the second example.

The operation of the storage battery pack 100 in the present example issuch that when abnormality of the storage battery pack 100 is detected(S201), an external entity is notified of an occurrence of theabnormality via the displayer 109 c (S202). In the present example, asillustrated in FIG. 8(a), an LED serving as the abnormality displayer109 c is lit to notify of an occurrence of abnormality.

Here, when an operator performs ON operation for a switch serving as thereceiver 114 (S203), the switch 103 is closed (ON) by the controller107, and the circuit 116 is activated and the remaining power of thesecondary battery 101 is consumed by the power consumer 105 (S204). Inaddition, an external entity is notified that the remaining power of thesecondary battery 101 is being consumed (S205). It is to be noted thatthe consumption of the remaining power of the secondary battery 101 inS204 is specifically the same as in the first example. Also, thenotification in S205 is the same as in the first example. Examples of anoperator include a user, a collection contractor, a waste disposalcontractor of the storage battery pack 100.

When the switch 103 is opened (OFF) by the controller 107, and theoperation of the circuit 116 is stopped, the consumption of theremaining power of the secondary battery 101 is completed (S206). Anexternal entity is notified that the consumption of the remaining powerof the secondary battery 101 is completed (S207). In S206, theconsumption of the remaining power of the secondary battery 101 isterminated in a state where the capacity is left that allows thesubsequent operation (S209) of the storage battery pack 100 to beperformed. The notification in S207 is specifically the same as in thefirst example.

Next, an operator operates the information terminal 300 to command thestorage battery pack 100 to check the remaining capacity of the storagebattery pack 100 (S208). The storage battery pack 100 receives thecommand via the communicator 111, and the controller 107 transmitsinformation indicating the remaining capacity of the secondary battery101 held in the storage 106 to the information terminal 300 via thecommunicator 111 (S209). The information terminal 300 displays theabove-mentioned received information on a screen (S210). In the presentexample, as illustrated in FIG. 8(c), the information on the remainingcapacity of the storage battery pack 100 is displayed as a ratio (%) ofthe remaining capacity with respect to the capacity at full charge ofthe storage battery pack 100. In calculation of the ratio, when thevoltage of the secondary battery 101 is the discharge cutoff voltage(for instance, 3.2 V), the ratio is not 0%, but when the voltage is 0 V,the ratio is 0%.

Third Example

Unlike the first example, in a storage battery pack 100 in a thirdexample, the receiver 114 is a communicator that performs wirelesscommunication with the information terminal 300. In the present example,the receiver 114 is a communicator that performs short-distance wirelesscommunication such as Bluetooth (registered trademark), Zigbee(registered trademark), NFC, and Wi-Fi, and communicates with aninformation terminal. It is to be noted that the receiver 114 may be acommunicator that performs wireless communication such as LTE which hasa longer communication distance than short-distance wirelesscommunication. The configuration except for this is the same as thesystem configuration of the storage battery pack 100 in the firstexample illustrated in FIG. 4.

Next, the operation of the storage battery pack 100 in the third examplewill be described.

FIG. 10 is a diagram illustrating the operational flow of the storagebattery pack in the third example.

FIG. 11 is a flow chart illustrating the operation of the storagebattery pack in the third example.

The operation of the storage battery pack 100 in the present example issuch that when abnormality of the storage battery pack 100 is detected(S301), an external entity is notified of an occurrence of theabnormality by the storage battery pack 100 (S302). In the presentexample, the notification is made by the abnormality displayer 109 c.Specifically, as illustrated in FIG. 10(a), an LED serving as theabnormality displayer 109 c is lit to notify of an occurrence ofabnormality. When notification of abnormality is made, an operatoroperates the information terminal 300 to check the detail of theabnormality (S303). Specifically, a check request for the detail of theabnormality is transmitted to the receiver 114 from the informationterminal 300 by an operation of an operator. When the receiver 114receives the above-mentioned check request, information (for instance,impact abnormality) indicating the detail of the abnormality held in thestorage 106 is transmitted to the information terminal 300 by thecontroller 107, and the information is displayed on the screen of theinformation terminal 300.

Here, when an operator operates the information terminal 300 to commandthe power consumer 105 to consume the remaining power of the secondarybattery 101 (S304), the switch 103 is closed (ON) by the controller 107,and the circuit 116 is activated and the remaining power of thesecondary battery 101 is consumed by the power consumer 105 (S305). Inaddition, an external entity is notified that the remaining power of thesecondary battery 101 is being consumed (S306). The consumption of theremaining power of the secondary battery 101 in S305 is specifically thesame as in the first example. The notification in S306 is specificallythe same as in the first example. Examples of an operator include auser, a collection contractor, a waste disposal contractor of thestorage battery pack 100. The above-mentioned command by an operatorcauses a collection contractor 302 to be notified that the storagebattery pack 100 is scheduled to be discarded (S307). In the presentexample, specifically, information indicating that the storage batterypack 100 is scheduled to be discarded is transmitted from theinformation terminal 300 to the server system 301 which notifies thecollection contractor 302 of the information.

When the switch 103 is opened (OFF) by the controller 107, and theoperation of the circuit 116 is stopped, the consumption of theremaining power of the secondary battery 101 is completed (S308). Also,an external entity is notified that the consumption of the remainingpower of the secondary battery 101 is completed (S309). The notificationin S309 is specifically the same as in the first example.

Next, when an operator operates the information terminal 300 to commandthe storage battery pack 100 to check the remaining capacity of thestorage battery pack 100, the information indicating the remainingcapacity of the secondary battery 101 is displayed on the screen of theinformation terminal 300 (S310 to S312). Specifically, the detail of thedisplay is the same as in the second example.

Fourth Example

A storage battery pack 100 in a fourth example will be described. Thesystem configuration of the storage battery pack 100 in the presentexample is the same as in the third example. In other words, thereceiver 114 is a communicator that performs wireless communication withthe information terminal 300.

Next, the operation of the storage battery pack 100 in the fourthexample will be described.

FIG. 12 is a diagram illustrating the operational flow of the storagebattery pack in the fourth example.

FIG. 13 is a flow chart illustrating the operation of the storagebattery pack in the fourth example.

The operation of the storage battery pack 100 in the present example issuch that when abnormality of the storage battery pack 100 is detected(S401), an external entity is notified of an occurrence of theabnormality by the storage battery pack 100 (S402). When notification ofabnormality is made, an operator operates the information terminal 300to check the detail of the abnormality (S403). The notification of theabnormality and the check of the detail of the abnormality arespecifically the same as in the third example.

Here, when an operator operates the information terminal 300 to commandthe power consumer 105 to consume the remaining power of the secondarybattery 101 (S404), the switch 103 is closed (ON) by the controller 107,and the circuit 116 is activated and the remaining power of thesecondary battery 101 is consumed by the power consumer 105 (S405). Inaddition, an external entity is notified that the remaining power of thesecondary battery 101 is being consumed (S406). The consumption of theremaining power of the secondary battery 101 in S405 is specifically thesame as in the first example. Also, in S406, the notification by theremaining amount displayer 109 b and the notification to the informationterminal via the receiver 114 are made. Specifically, as illustrated inFIG. 12(b), a light emitter serving as the remaining amount displayer109 b blinks, thereby notifying an external entity that the remainingpower of the secondary battery 101 is being consumed. Also, informationindicating that the remaining power of the secondary battery is beingconsumed is transmitted by the controller 107 to the informationterminal 300 via the receiver 114, and the information is displayed onthe information terminal 300. Examples of an operator include a user, acollection contractor, a waste disposal contractor of the storagebattery pack 100.

When the switch 103 is opened (OFF) by the controller 107, and theoperation of the circuit 116 is stopped, the consumption of theremaining power of the secondary battery 101 is completed (S407). Also,an external entity is notified that the consumption of the remainingpower of the secondary battery 101 is completed (S408). In the presentexample, the notification by the remaining amount displayer 109 b andthe notification to the information terminal 300 via the receiver 114are made. Specifically, as illustrated in FIG. 10(c), the light emitterserving as the remaining amount displayer 109 b stops blinking, therebynotifying an external entity that the consumption of the remaining powerof the secondary battery 101 is completed. Also, information indicatingthat consumption of the remaining power of the secondary battery iscompleted is transmitted by the controller 107 to the informationterminal 300 via the receiver 114, and the information is displayed onthe information terminal 300.

Also, when the consumption of the remaining power of the secondarybattery 101 is completed, the information terminal 300 is notified ofinformation to prompt contact with a collection contractor (S409).Specifically, as illustrated in FIG. 12(c), when the consumption of theremaining power of the secondary battery 101 is completed, thecontroller 107 notifies via the receiver 114 the information terminal300 of information to prompt contact with a collection contractor. Theinformation includes, for instance, a message to prompt contact with acollection contractor, and the information may further include the nameof a collection contractor and contact information. Several names ofcollection contractors and their contact information may be provided,and those may be displayed as a list on the screen of the informationterminal 300.

Fifth Example

A storage battery pack 100 in a fifth example will be described. Thesystem configuration of the storage battery pack 100 in the presentexample is the same as in the first example. In other words, thereceiver 114 is a switch that receives an operation of an operator.

Next, the operation of the storage battery pack 100 in the fifth examplewill be described.

FIG. 14 is a diagram illustrating the operational flow of the storagebattery pack in the fifth example.

FIG. 15 is a flow chart illustrating the operation of the storagebattery pack in the fifth example.

In the storage battery pack 100 in the present example, informationindicating that the life of the storage battery pack 100 is reached istransmitted to the information terminal 300 from the server system 301(S501), and the information is displayed on the screen of theinformation terminal 300 (S502). Although not illustrated in FIG. 14 andFIG. 15, a notifier provided in the storage battery pack 100 may notifyan external entity that the battery life is reached. For instance, theabnormality displayer 109 c or the remaining amount displayer 109 b maybe used as the notifier, and a notifier different from these displayersmay be separately provided.

When an operator who has checked that the battery life is reachedperforms ON operation for a switch serving as the receiver 114 on thescreen of the information terminal 300 (S503), the remaining power ofthe secondary battery 101 is consumed by the power consumer 105 (S504),and an external entity is notified that the remaining power of thesecondary battery 101 is being consumed (S505). The consumption of theremaining power of the secondary battery 101 in S504 is specifically thesame as in the first example. The notification in S505 is specificallythe same as in the first example as illustrated in FIG. 14(b). Examplesof an operator include a user, a collection contractor, a waste disposalcontractor of the storage battery pack 100.

When the switch 103 is opened (OFF) by the controller 107, and theoperation of the circuit 116 is stopped, the consumption of theremaining power of the secondary battery 101 is completed (S506). Also,an external entity is notified that the consumption of the remainingpower of the secondary battery 101 is completed (S507). The notificationin S507 is specifically the same as in the first example as illustratedin FIG. 14(c).

Although not described above, similarly to the second example, thestorage battery pack 100 may further include the communicator 111, andafter the consumption of the remaining power of the secondary battery101 is completed, the remaining capacity of the storage battery pack 100may be checked via the information terminal 300.

Sixth Example

A storage battery pack 100 in a sixth example will be described. Thesystem configuration of the storage battery pack 100 in the presentexample is the same as in the third example. In other words, thereceiver 114 is a communicator that performs wireless communication withthe information terminal 300.

Next, the operation of the storage battery pack 100 in the sixth examplewill be described.

FIG. 16 is a diagram illustrating the operational flow of the storagebattery pack in the sixth example.

FIG. 17 is a flow chart illustrating the operation of the storagebattery pack in the sixth example.

The operation of the storage battery pack 100 in the present example issuch that information indicating that the life of the storage batterypack 100 is reached is transmitted to the information terminal 300 fromthe server system 301 (S601), and the information is displayed on thescreen of the information terminal 300 (S602). Although not illustratedin FIG. 16 and FIG. 17, a notifier provided in the storage battery pack100 may notify an external entity that the battery life is reached.Specifically, the detail of the notification is the same as in the fifthexample.

An operator, who has checked that the battery life is reached on thescreen of the information terminal 300, operates the informationterminal 300, and commands the power consumer 105 to consume theremaining power of the secondary battery 101 (S603). Then, the switch103 is closed (ON) by the controller 107, and the circuit 116 isactivated and the remaining power of the secondary battery 101 isconsumed by the power consumer 105 (S604). In addition, an externalentity is notified that the remaining power of the secondary battery 101is being consumed (S605). The consumption of the remaining power of thesecondary battery 101 in S604 is specifically the same as in the firstexample. Also, the notification in S605 is specifically the same as inthe first example. Examples of an operator include a user, a collectioncontractor, a waste disposal contractor of the storage battery pack 100.The above-mentioned command by an operator causes a collectioncontractor 302 to be notified that the storage battery pack 100 isscheduled to be discarded (S606). The notification in S606 isspecifically the same as in the third example.

When the switch 103 is opened (OFF) by the controller 107, and theoperation of the circuit 116 is stopped, the consumption of theremaining power of the secondary battery 101 is completed (S607). Also,an external entity is notified that the consumption of the remainingpower of the secondary battery 101 is completed (S608). Specifically,the notification is the same as in the first example as illustrated inFIG. 16(c).

Next, when an operator operates the information terminal 300 to commandthe storage battery pack 100 to check the remaining capacity of thestorage battery pack 100, the information indicating the remainingcapacity of the secondary battery 101 is displayed on the screen of theinformation terminal 300 (S609 to S611). Specifically, the detail of thedisplay is the same as in the second example.

Seventh Example

A storage battery pack 100 in a seventh example will be described.Unlike the first to fourth examples, in the storage battery pack 100 inthe present example, when abnormality is detected by the abnormalitydetector 112, the controller 107 controls the power consumer 105 toconsume the remaining power of the secondary battery 101 even with nocommand to the storage battery pack 100 via the receiver 114. Otheroperational flows are the same as in the first to fourth examples.

Eight Example

A storage battery pack 100 in an eighth example will be described. Thestorage battery pack 100 in the present example is the storage batterypack 100 according to any one of the second to sixth examples, in whichwhen the consumption of the remaining power of the secondary battery 101by the power consumer 105 is completed, the controller 107 transmitsinformation indicating the remaining capacity of the secondary battery101 to an external device via the communicator 111 (or the communicatoras the receiver 114). The information indicating the remaining capacityof the secondary battery 101 is held in the storage 106. Althoughexamples of an external device include the information terminal 300, andthe server system 301, the external device is not limited to these andmay be in any form.

Also, after the consumption of the remaining power of the secondarybattery 101 is completed, the controller 107 may transmit theinformation indicating the remaining capacity of the secondary battery101 to an external device. In this case, the consumption of theremaining power of the secondary battery 101 is terminated in a statewhere the capacity is left that allows transmission of the informationindicating the remaining capacity of the secondary battery 101 to anexternal device.

Ninth Example

A storage battery pack 100 in a ninth example will be described. Thestorage battery pack 100 in the present example is the storage batterypack 100 according to any one of the first to eighth examples, in whichthe secondary battery 101 includes cells, and before the voltages of allthe cells reach 0 V, the controller 107 stops the consumption of theremaining power of the secondary battery 101 by the power consumer 105.

When the secondary battery includes cells, it is preferable that thecells have an uniform degree of deterioration (SOH). However, the cellsexhibit different degrees of deterioration as the storage battery packis used more often. Therefore, when the remaining power of the secondarybattery is consumed, the voltages of the cells are varied, and in somecells, the voltage reaches 0 V relatively early. When those cells withthe reached 0 V are further discharged, polarity inversion occurs, andthere arises a problem in safety.

Thus, as in the present example, consumption of the power of thesecondary battery by the power consumer is terminated before thevoltages of all the cells reach 0 V, thereby reducing the number ofcells in which polarity inversion occurs and improving the safetycompared with the case where the power is discharged until the voltagesof all the cells reach 0 V.

In the storage battery pack 100 in the present example, when the voltageof at least one cell is 0 V and before the voltages of all the cellsreach 0 V, the controller 107 may stop the consumption of the remainingpower of the secondary battery 101 by the power consumer 105.

Tenth Example

A storage battery pack 100 in a tenth example will be described. Thestorage battery pack 100 in the present example is the storage batterypack 100 according to any one of the first to ninth examples, in whichwhen the storage battery pack 100 is connected to an electricalappliance via the connector and the power consumer 105 is consuming theremaining power of the secondary battery 101, the electrical appliancealso consumes the remaining power of the secondary battery 101 until thevoltage of the secondary battery 101 reaches a discharge cutoff voltage.In this manner, completion of the consumption of the remaining power ofthe secondary battery 101 may be made earlier.

The above-mentioned electrical appliance may be an electrical appliancesuch as an electric mobile body, an air conditioner, a lighting device,that operates using the power of the secondary battery 101. Also, aslong as the above-mentioned electrical appliance is provided with a loadfor discharge internally, the electrical appliance may not operate usingthe power of the secondary battery 101. For instance, theabove-mentioned electrical appliance may be the charging device 200 aslong as a load for discharge is internally provided in the chargingdevice 200.

Second Embodiment

At the start of charging the secondary battery, the storage battery pack100 may discharge (learning discharge) the secondary battery fordetermining whether or not continuous use of the secondary battery isallowed, by the control of the controller 107. Hereinafter, the storagebattery pack 100 according to a second embodiment will be described. Inthe following second embodiment, points different from the firstembodiment will be mainly described, and a description of the componentsalready described in the first embodiment is omitted.

First, the storage battery pack according to the second embodiment willbe described. FIG. 18 is a perspective view of the storage battery packin the second embodiment.

The storage battery pack 100 includes a discharge displayer 109 d. Thedischarge displayer 109 d displays at least one of informationindicating that the controller 107 of the storage battery pack 100 is inlearning discharge and information indicating whether or not continuoususe of the secondary battery 101 is allowed. Specifically, the dischargedisplayer 109 d includes an LED, and blinks the LED during learningdischarge, and lights up the LED when it is determined that continuoususe of the secondary battery 101 is not possible. The detail of thelearning discharge and determination as to whether or not continuous useof the secondary battery is allowed will be described later.

FIG. 19 is a block diagram illustrating the system configuration of thestorage battery pack 100 according to the second embodiment.

As illustrated in FIG. 19, the storage battery pack 100 includes acurrent measure 110.

The current measure 110 is a current sensor disposed at a position whichallows measurement of both the current flowing from the secondarybattery 101 to an electrical appliance connected to the connector 102,and the current flowing from the secondary battery 101 to the powerconsumer 105. Specifically, the current measure 110 is disposed betweenthe secondary battery 101 and the power consumer 105 on the circuit.Measurement data of a current value measured by the current measure 110is transmitted to the controller 107. For instance, when the secondarybattery 101 is to be completely discharged, the controller 107 observesthe current value measured by the current measure 110, and dischargesthe secondary battery 101 until the current value becomes sufficientlysmall.

In the storage battery pack 100 in the present embodiment, thecontroller 107 determines whether or not continuous use of the secondarybattery 101 is allowed, based on the amount of discharge of thesecondary battery 101, the discharge causing the value indicating theremaining capacity of the secondary battery 101 to change from the valueindicating full charge to the first threshold value or less.

Upon detecting the start of charge (for instance, signal indicating thestart of charge) of the secondary battery 101 in a state where theconnector 102 is connected to the charging device 200, the controller107 performs learning discharge. The learning discharge is suchdischarge (first discharge) that causes the secondary battery 101 todischarge using the power consumer 105 until the value indicating theremaining capacity of the secondary battery 101 falls below the firstthreshold value for determining whether or not continuous use of thesecondary battery 101 is allowed.

In addition, when it is determined that continuous use of the secondarybattery 101 is not possible, the controller 107 causes the powerconsumer 105 to further consume the remaining power of the secondarybattery 101. The consumption of the remaining power of the secondarybattery 101 may be made after the receiver 114 receives a command forthe remaining power consumption of the secondary battery 101, or may bemade by the control of the controller 107 without receiving theabove-mentioned command by the receiver 114. In the present embodiment,the secondary battery 101 is discharged using the power consumer 105until the value indicating the remaining capacity of the secondarybattery 101 falls below the third threshold value which is less than thefirst threshold value (second discharge). The third threshold value maybe a value less than the discharge cutoff voltage. The third thresholdvalue may be a value for which the secondary battery 101 is in anunusable state. Here, an unusable state of the secondary battery 101means a state where the storage battery pack 100 is unable to be used asa battery even if it is charged after the consumption of the remainingpower of the secondary battery 101 by the power consumer 105 iscompleted.

The detail of the determination as to whether or not continuous use isallowed, the first discharge, and the second discharge mentioned abovewill be described later.

[Basic Operation]

Next, the basic operation of the storage battery pack 100 will bedescribed. FIG. 20, FIG. 21, and FIG. 22 are diagrams for explaining thebasic operation of the storage battery pack 100.

When power is supplied to an electrical appliance connected to theconnector 102, the controller 107 turned off the switch 103 and turnedon the switch 104 as illustrated in FIG. 20. The current value at thispoint is measurable by the current measure 110.

When the secondary battery 101 is charged, the controller 107 alsoturned off the switch 103 and turned on the switch 104. To achieve afull charge state of the secondary battery 101, the controller 107charges the secondary battery 101 until the voltage value of thesecondary battery 101 reaches an upper limit (for instance, 4.1 V)indicating full charge. The upper limit here may be a standard value(charge cutoff voltage) for charge of the secondary battery 101.

When the secondary battery 101 is discharged using the power consumer105, that is, when the first discharge and the second dischargementioned above are performed, the controller 107 turned on the switch103 and turned off the switch 104 as illustrated in FIG. 21. The currentvalue at this point is measurable by the current measure 110.

Here, in the first discharge, the controller 107 discharges thesecondary battery 101 until the voltage value of the secondary battery101 reaches the first threshold value (for instance, 3.3 V). It is to benoted that the first threshold value is greater than the dischargecutoff voltage (for instance, 3.2 V) which is a standard value thatallows discharge of the secondary battery 101. Alternatively, in thefirst discharge, the secondary battery 101 may be discharged until thevoltage value of the secondary battery 101 reaches the discharge cutoffvoltage.

In the second discharge, the controller 107 discharges the secondarybattery 101 until the voltage value of the secondary battery 101 fallsbelow the third threshold value which is less than the first thresholdvalue. Alternatively, in the second discharge, the secondary battery 101may be discharged until the voltage value falls below the dischargecutoff voltage, which is a state where the secondary battery 101 isunable to be used again. Although the third threshold value is, forinstance, 0 V, an unusable state of the secondary battery 101 may beachieved using a voltage (for instance, approximately 1.5 V) lower thanthe discharge cutoff voltage.

It is to be noted that in order to speed up discharging of the secondarybattery 101, the controller 107 may turn on the switch 103 and may turnoff the switch 104 as illustrated in FIG. 22. In other words, when anelectrical appliance is connected to the connector 102, the secondarybattery 101 may be discharged using both the power consumer 105 and theelectrical appliance connected to the connector 102. In this manner, itis possible to speed up discharging of the secondary battery 101. It isto be noted that the electrical appliance connected to the connector 102is an electrical appliance that operates using the power of thesecondary battery 101, for instance. Although the charging device 200 isnot an electrical appliance that operates using the power of thesecondary battery 101, when a load for discharge of the secondarybattery 101 is provided in the charging device 200, such a load may beused for the discharge of the secondary battery 101. Therefore, theabove-mentioned electrical appliance may include the charging device 200in the case where a load for discharge is internally provided. Dischargeusing the power consumer 105 and the electrical appliance may beperformed in any one of the first discharge and the second discharge.Although the voltage value is used as a value that indicates theremaining capacity of the secondary battery 101 in the above-describedexample, without being limited to this, the remaining capacity itselfmay be used. For calculation of the remaining capacity itself, a valueobtained by time-integrating the current value measured by the currentmeasure 110 is used.

[First Discharge and Second Discharge]

Next, the first discharge and the second discharge, which arecharacteristic configuration of the storage battery pack 100, will bedescribed in detail.

The first discharge refers to the discharge that causes the secondarybattery 101 to discharge until a predetermined capacity (predeterminedvoltage value) is reached in order to determine whether or notcontinuous use of the secondary battery 101 is allowed. The storagebattery pack 100 is characteristic in that when the secondary battery101 is charged, such learning discharge is performed using the powerconsumer 105 provided in the storage battery pack 100. FIG. 23 is agraph for explaining the first discharge and the second discharge of thesecondary battery 101. FIG. 23 is a graph schematically illustrating atemporal change in the capacity (remaining capacity) of the secondarybattery 101.

In the second embodiment, determination as to whether or not continuoususe is allowed is made based on whether or not the maximum capacity ofthe secondary battery 101 is less than a predetermined capacity D. Here,the maximum capacity of the secondary battery 101 is the differencebetween the capacity (the capacity when charging is performed until thevoltage reaches a predetermined upper limit) at the time of full chargeand a predetermined capacity C (the capacity when the voltage reachesthe first threshold value).

The maximum capacity of the secondary battery 101 is calculated based onthe amount of discharge that causes the capacity at the time of fullcharge to decrease to the predetermined capacity C. Specifically, thecontroller 107 stores the above-mentioned amount of discharge in thestorage 106, and accumulated stored amount of discharge is calculated asthe maximum capacity of the secondary battery 101.

Here, as illustrated in FIG. 23, when the secondary battery 101 isstarted to be used, the capacity at the time of full charge is apredetermined capacity A. However, the capacity gradually decreases dueto repeated charge and discharge, and thus, the maximum capacity of thesecondary battery 101 also decreases. When the maximum capacity of thesecondary battery 101 falls below the predetermined capacity D, it isdetermined that continuous use of the secondary battery 101 is notpossible.

As described above, in order to calculate the maximum capacity of thesecondary battery 101, the secondary battery 101 has to be discharged tothe predetermined capacity C.

Thus, in the storage battery pack 100, upon detecting a signalindicating the start of charge, when the remaining capacity of thesecondary battery 101 is greater than the predetermined capacity C andless than or equal to the predetermined capacity B, the controller 107performs the first discharge until the capacity of the secondary battery101 reduces to the predetermined capacity C. In other words, upondetecting a signal indicating the start of charge, when the voltage ofthe secondary battery 101 is greater than the first threshold value andless than or equal to the second threshold value (for instance, 3.5 V),the controller 107 performs learning discharge. The second thresholdvalue is a value less than the predetermined upper limit that indicatesfull charge.

In this manner, the first discharge is performed when the remainingcapacity of the secondary battery 101 is small. Thus, the controller 107is able to cause the secondary battery 101 to discharge in a short time.

Since the capacity of the secondary battery 101 is not likely todecrease significantly in a short time, determination as to whether ornot continuous use is allowed does not have to be made frequently.Frequent learning discharge may cause a disadvantage that deteriorationof the secondary battery 101 is promoted.

Thus, in the first embodiment, the history of learning discharge isstored in the storage 106, and the controller 107 performs subsequentlearning discharge when a predetermined period T has elapsed since thelast learning discharge is performed.

For instance, in FIG. 23, a signal indicating the start of charge isdetected at each of timing t1, t2, t3, and t4, and at each timing, theremaining capacity of the secondary battery 101 greater than thepredetermined capacity C and less than or equal to the predeterminedcapacity B.

Here, although learning discharge is started at timing t1 and t3,learning discharge is not performed at timing t2 and only charge isperformed because the predetermined period T has not elapsed at timingt1 since learning discharge is started. Similarly, at timing t4,learning discharge is not performed because the predetermined period Thas not elapsed since learning discharge is started at timing t3.

In this manner, in the first embodiment, learning discharge of thesecondary battery 101 is performed not for every charge of the secondarybattery 101 but based on the condition of lapse of a predeterminedperiod. Therefore, unnecessary discharge may be reduced in a situationwhere the time interval between charges is short and a variation of thebattery life is estimated to be low. Furthermore, it is possible tosuppress deterioration (reduction in the life) of the secondary battery101 by reducing the number of times of discharge.

Next, the second discharge will be described with reference to FIG. 23.

When the maximum capacity of the secondary battery 101 falls below thepredetermined capacity D and it is determined that continuous use of thesecondary battery 101 is not possible, the controller 107 performs thesecond discharge. Specifically, the controller 107 causes the secondarybattery 101 to discharge using the power consumer 105 until theremaining capacity of the secondary battery 101 reaches a predeterminedcapacity E. In other words, the controller 107 causes the secondarybattery 101 to discharge using the power consumer 105 until the valueindicating the remaining capacity of the secondary battery 101 fallsbelow the third threshold value which is less than the first thresholdvalue.

For instance, in FIG. 23, as a result of performing learning discharge,it is determined at timing t6 that continuous use of the secondarybattery 101 is not possible. Therefore, the controller 107 performs thesecond discharge.

The first discharge and the second discharge explained above will befurther described using a flow chart. FIG. 24 is a flow chart of thefirst discharge and the second discharge.

First, the controller 107 detects a signal indicating the start ofcharge of the secondary battery 101 (S11). The controller 107 detects,for instance, connection of the storage battery pack 100 to the chargingdevice 200 as a signal indicating the start of charge. Also, after thestorage battery pack 100 is connected to the charging device 200, asignal indicating the start of charge may be transmitted to thecontroller 107 triggered by an operation (for instance, depressing acharge start button) performed on the storage battery pack 100 or thecharging device 200.

Upon detecting a signal indicating the start of charge (Yes in S11), thecontroller 107 refers to the history of learning discharge in thestorage 106 and checks to see whether or not a predetermined period haselapsed since the last learning discharge (S12).

When a predetermined period has elapsed since the last learningdischarge (Yes in S12), the controller 107 checks the remaining capacityof the secondary battery 101 (S13). When the remaining capacity of thesecondary battery 101 is less than or equal to the predeterminedcapacity B (Yes in S13), the controller 107 performs learning discharge(S14).

The learning discharge is performed until the remaining capacity reachesthe predetermined capacity C (No in S15). When the remaining capacityreaches the predetermined capacity C (Yes in S15), the controller 107stops the learning discharge (S16), and determines whether or notcontinuous use of the secondary battery 101 is allowed (S17).

When it is determined that continuous use of the secondary battery 101is allowed (No in S17), the secondary battery 101 is charged (S18). Inaddition, when the predetermined period has not elapsed since the lastlearning discharge (No in S12) or when the remaining capacity of thesecondary battery 101 is greater than the predetermined capacity B (Noin S13), the secondary battery 101 is charged.

When it is determined that continuous use of the secondary battery 101is not possible (Yes in S17), the controller 107 performs the seconddischarge (S19).

Effects

As described above, in the storage battery pack 100 according to thefirst embodiment, when a signal indicating the start of charge of thesecondary battery 101 is detected in a state where the connector 102 isconnected to the charging device 200, the first discharge is performed.

In this manner, the first discharge is performed at the time of charge,thus a user does not have to cause the secondary battery 101 to performlearning discharge separately in order to determine whether or notcontinuous use is allowed. Also, since learning discharge is performedon the secondary battery 101 at the time of charge when the amount ofstored power is estimated to be low, the time taken for the learningdischarge may be reduced.

Since the secondary battery is discharged at the appropriate timing asdescribed above, the time, in which the storage battery pack 100 isavailable to a user for power supply to an appliance, is secured, andthus the convenience of the storage battery pack 100 may be improved.

Also, in the storage battery pack 100, when it is determined thatcontinuous use of the secondary battery 101 is not possible, the seconddischarge is performed.

Even when the secondary battery 101 is discarded after being dischargeduntil the discharge cutoff voltage is reached, the remaining capacity ofthe secondary battery 101 is still left, and thus a handler of thesecondary battery 101 may have electric shock or suffer burns due toheat generation during discard processing. Particularly, when thesecondary battery 101 is a lithium-ion battery, such a dangerousoccurrence is probable, and thus a safe method of discarding batteriesis demanded.

In the second discharge, the secondary battery 101, which is determinedto be unable to be used continuously, is discharged until the voltagefalls below the discharge cutoff voltage, thereby achieving an unusablestate (a state unable to be used as a battery even after recharged) ofthe storage battery pack 100. In such a situation, it is possible toreduce the possibility of occurrence of burns, electric shock, and thusthe safety in discarding the storage battery pack 100 may be improved.

Modification

In the second embodiment, in order to start learning discharge, thefollowing condition has to be satisfied: a first predetermined period Thas elapsed since the last learning discharge and the voltage of thesecondary battery 101 is less than or equal to the second thresholdvalue. In this situation, for instance, when learning discharge has notbeen performed for at least a second predetermined period (for instance,2T) longer than the predetermined period T, the second threshold valuemay be increased. The second threshold value is increased from 3.5 V to3.7 V, for instance.

Thus, when learning discharge has not been performed for a long period,learning discharge tends to be performed, and thus determination as towhether or not continuous use is allowed may be made more reliably.

Third Embodiment

A storage battery pack 100 according to the third embodiment will bedescribed. In the following third embodiment, points different from thesecond embodiment will be mainly described, and a description of thecomponents already described in the second embodiment is omitted.

The storage battery pack 100 according to the third embodiment includesa communicator that communicates with an external device. The systemconfiguration of the storage battery pack 100 is the same as the systemconfiguration of the storage battery pack described with reference toFIG. 7.

In the storage battery pack 100 in the present embodiment, thecommunicator 111 transmits data of state value indicating the state ofthe secondary battery 101 to an external device. The communicator 111receives information indicating a state of the secondary battery 101from an external device, and thus the controller 107 is able to checkthe state of the secondary battery 101, the state being determined bythe external device based on the above-described data. Here, examples ofan external device include a server system, an information terminal, anda charging device.

The communicator 111 may transmit an amount of discharge of thesecondary battery 101 to an external device, and may receive from theexternal device information indicating whether or not continuous use ofthe secondary battery 101 is allowed, the discharge causing the valueindicating the remaining capacity of the secondary battery 101 to changefrom the value indicating full charge to the first threshold value orless, for instance. In short, determination as to whether or notcontinuous use of the secondary battery 101 is allowed may be made by anexternal device.

The communicator 111 may transmit to an external device, for instance,at least one of information indicating that the controller 107 is inlearning discharge and information indicating whether or not continuoususe of the secondary battery 101 is allowed. Thus, it is possible for anexternal device to hold information indicating the state of thesecondary battery 101.

In addition, the communicator 111 receives a signal that controls theswitch 103 and the switch 104 from an external device, thereby making itpossible to switch (remote control) between charge and discharge of thesecondary battery 101.

Fourth Embodiment

In a fourth embodiment, typically, the power consumer 105 may alsoinclude a resistor for cell balance. Hereinafter, a storage battery pack100 according to the fourth embodiment will be described. In thefollowing fourth embodiment, points different from the first and secondembodiments will be mainly described, and the configuration other thanthis is the same as the configuration of one of the first embodiment andthe second embodiment, and thus a specific description is omitted.

FIG. 25 is a diagram for explaining a resistor for cell balance. FIG. 25is a schematic diagram and the number of cells is simplified for thesake of explanation.

As illustrated in FIG. 25, the secondary battery 101 is formed of, forinstance, a cell 101 a, a cell 101 b, and a cell 101 c connected inseries.

A storage battery pack 100 in the present embodiment includes oneresistor for cell balance and one switch for each cell in order toadjust the voltages between the cells. The controller 107 controls ON orOFF of switches provided correspondingly to the cells.

For instance, when the switch 128 a is turned ON or turned OFF by thecontroller 107, the electrical connection between the resistor 118 a forcell balance and the cell 101 a is turned ON or turned OFF. Similarly,when the switch 128 b is turned ON or turned OFF, the electricalconnection between the resistor 118 b for cell balance and the cell 101b is turned ON or turned OFF. When the switch 128 c is turned ON orturned OFF, the electrical connection between the resistor 118 c forcell balance and the cell 101 c is turned ON or turned OFF.

With the configuration described above, the controller 107 is capable ofdischarging each cell individually and adjusting the voltages betweenthe cells. Such a resistor for cell balance may be used as the powerconsumer 105.

Fifth Embodiment

The storage battery pack 100 may include a heater (heating element) asthe power consumer 105. Hereinafter, a storage battery pack including aheater according to a fifth embodiment will be described. In thefollowing fifth embodiment, points different from the first embodimentwill be mainly described, and a description of the components alreadydescribed in the first embodiment is omitted.

FIG. 26 is a perspective view illustrating the internal configuration ofthe storage battery pack according to the fifth embodiment. FIG. 27 is aview illustrating the configuration of the heater according to the fifthembodiment. It is to be noted that illustration of the connector 102 isomitted in FIG. 26.

As illustrated in FIG. 26, the storage battery pack 100 according to thefifth embodiment differs from the storage battery pack 100 according tothe first embodiment in that the power consumer 105 is a heating elementthat generates heat by consuming the power discharged by the secondarybattery 101. In addition, a heater 140 as an example of a heatingelement surrounds the periphery of the secondary battery 101.

As illustrated in FIG. 27, specifically, the heater 140 includes anexothermic element 141, and an insulator 142 that covers the exothermicelement 141. The exothermic element 141 is connected to one end of alead wire 143, and the other end of the lead wire 143 is connected tothe secondary battery 101. The lead wire 143 is connected to the switch103, and the switch 103 switches between ON and OFF of electricalconnection between the secondary battery 101 and the heater 140 based onthe control of the controller 107.

With the configuration like this, when the controller 107 performscontrol to cause the secondary battery 101 to discharge, the secondarybattery 101 is heated by the heat generated by the heater 140. Thus, itis possible to protect against performance degradation caused bydecrease in the temperature of the secondary battery 101.

Alternatively, the storage battery pack 100 may include a temperaturedetector (not illustrated) that detects the temperature inside thestorage battery pack 100. In this case, when the temperature inside thestorage battery pack 100 decreases, the controller 107 discharges thesecondary battery 101.

Specifically, when the temperature detector detects that the temperatureinside the storage battery pack 100 is less than or equal to a thresholdvalue temperature, the controller 107 discharges the secondary battery101, and heater 140 consumes power and generates heat. Since the heater140 surrounds the periphery of the secondary battery 101, the secondarybattery 101 is heated by the heat generated by the heater 140.Consequently, when the temperature is low, it is possible to avoiddecrease of the temperature of the secondary battery 101. The control ofsuch controller 107 will be described with reference to FIG. 28. FIG. 28is a graph for explaining an operational example of the storage batterypack according to the fifth embodiment.

As illustrated in FIG. 28, when it is detected that the temperatureinside the storage battery pack 100 is less than or equal to a thresholdvalue temperature TO, the controller 107 causes the secondary battery101 to discharge, and the heater 140 consumes power and generates heat.At this point, the threshold value temperature T0 is set higher than aboundary temperature Tth at or below which the secondary battery 101 isunable to be used.

Subsequently, when it is detected that the temperature inside thestorage battery pack 100 is higher than or equal to a threshold valuetemperature T0′ which is higher than the threshold value temperature T0,the controller 107 stops the discharge of the secondary battery 101. Inother words, the controller 107 stops generation of heat by the heater140.

When the secondary battery 101 is a lithium-ion battery, the boundarytemperature Tth, at or below which the secondary battery 101 is unableto be used, is approximately 0° C. Therefore, it is preferable that thethreshold value temperature T0 be set to approximately 10° C., and thethreshold value temperature T0′ be set to approximately 15° C. It is tobe noted that specific values of the temperatures Tth, T0, and T0′ areonly examples, and the temperatures are not limited to these examples.

With the configuration described above, it is possible to avoidtemperature decrease down to a temperature at which the secondarybattery 101 is unable to be used in a low temperature environment, andto control heat generation by the heater 140 to avoid excessive heatingof the secondary battery 101. In other words, it is possible to reduceunnecessary discharge of the secondary battery 101 and to protectagainst performance degradation of the secondary battery 101 at a lowtemperature.

It is to be noted that the heater 140 does not have to surround theperiphery of the secondary battery 101 in contact with the lateral facesthereof. The heater 140 may be mounted on a portion of the secondarybattery 101 as long as the heater 140 is able to heat the secondarybattery 101.

Other Embodiments

Although the first to fifth embodiments have been described above, thepresent disclosure is not limited to the first to fifth embodiments.

For instance, the storage battery pack may include an image displayerhaving a display screen, and the function of the displayer 109, whichhas been described in the embodiments, may be achieved by the imagedisplayer. FIG. 29 is a perspective view of the storage battery packincluding an image displayer.

The storage battery pack 100 illustrated in FIG. 29 includes an imagedisplayer 115. The image displayer 115 includes, for instance, a displaypanel such as an organic EL panel, an LCD panel.

The image displayer 115 is able to display the remaining capacity of thesecondary battery 101, information indicating that learning discharge isbeing performed, information indicating whether or not continuous use ofthe secondary battery 101 is allowed, and information indicatingabnormality of the storage battery pack 100. In addition, the imagedisplayer 115 includes a touch panel, and serves as a user interface. Inother words, the image displayer 115 also serves as the remaining amountdisplay button 109 a, and the receiver 114.

In the above-described embodiments, when abnormality occurs in thestorage battery pack 100, the receiver 114 receives a command andconsumption of the remaining power of the secondary battery 101 is made.However, without being limited to this, a command may be issued to thereceiver 114 at any timing, and consumption of the remaining power ofthe secondary battery 101 may be made.

In the above-described embodiments, each component may be formed bydedicated hardware, or may be implemented by executing a softwareprogram suitable for the component. Each component may be implemented bya program executor such as a CPU or a processor, that reads and executesa software program recorded on a storage medium such as a hard disk orsemiconductor memory.

In the above-described embodiments, the components may be circuits.These circuits may form a single circuits as a whole, or may be separatecircuits. Alternatively, these circuits may be general-purpose circuitsor may be dedicated circuits.

In the above-described embodiments, processing executed by a specificprocessor may be executed by another processor. For instance, thevoltage detector 108 may be implemented as a function of the controller107. The order of a plurality of processing may be changed or theplurality of processing may be executed concurrently.

For instance, the present disclosure may be implemented as a method ofcharging and discharging a storage battery pack.

The present disclosure is not limited to these embodiments or theirmodifications. The embodiments and their modifications to which variousalterations which will occur to those skilled in the art are made, andan embodiment constructed by a combination of components of differentembodiments and their modifications without departing from the spirit ofthe present disclosure are also included within the scope of the presentdisclosure.

The present disclosure is useful as a storage battery pack that is ableto discharge at appropriate timing.

What is claimed is:
 1. A storage battery pack comprising: a secondarybattery; a circuit that includes a power consumer which consumes powerof the secondary battery; terminals for charging to or discharging fromthe storage battery pack; a switching element that, when the voltage ofthe secondary battery reaches the discharge cutoff voltage, is opened tostop discharge of the secondary battery through the terminals; acontroller; and a memory including a set of executable instructionsthat, when executed by the controller causes the controller to perform afirst discharge operation including: activating the circuit and causingthe power consumer to consume a remaining power of the secondary batteryuntil a voltage of the secondary battery reaches a first threshold valuewhich is higher than the discharge cutoff voltage; and stopping, whenthe voltage of the secondary battery reaches the first threshold value,the first discharge operation, the memory including a set of executableinstructions that, when executed by the controller causes the controllerto perform a second discharge operation including: activating thecircuit and causing the power consumer to consume the remaining power ofthe secondary battery until the voltage of the secondary battery reachesa third threshold value which is lower than the discharge cutoffvoltage.
 2. The storage battery pack according to claim 1, wherein thecontroller performs the first discharge operation under a condition that(i) the storage battery pack is connected to a charging device, and (ii)the voltage of the secondary battery is lower than a second thresholdvalue which is higher than the first threshold value.
 3. The storagebattery pack according to claim 1, wherein the controller performs thefirst discharge operation under a condition that the storage batterypack is connected to a charging device, after the stopping the firstdischarge operation, the controller automatically closes the switchingelement to start charging to the secondary battery from the chargingdevice.
 4. The storage battery pack according to claim 1, wherein thecontroller performs the first discharge operation under a condition thatthe storage battery pack is connected to a charging device, after thestopping the first discharge operation, the controller automaticallycloses the switching element to start charging to the secondary batteryfrom the charging device, after the second discharge operation, thecontroller does not charge the secondary battery from the chargingdevice regardless of the connection to the charging device.
 5. Thestorage battery pack according to claim 2, wherein after the stoppingthe first discharge operation, the controller automatically closes theswitching element to start charging to the secondary battery from thecharging device.
 6. The storage battery pack according to claim 2,wherein after the stopping the first discharge operation, the controllerautomatically closes the switching element to start charging to thesecondary battery from the charging device, after the second dischargeoperation, the controller does not charge the secondary battery from thecharging device regardless of the connection to the charging device. 7.The storage battery pack according to claim 1, wherein the memoryincluding a set of executable instructions that, when executed by thecontroller causes the controller to perform the second dischargeoperation including: stopping, when the voltage of the secondary batteryreaches the third threshold value, the second discharge operation. 8.The storage battery pack according to claim 1, further comprising thesecondary battery includes a plurality of cells, wherein, the memoryincluding a set of executable instructions that, when executed by thecontroller causes the controller to perform the second dischargeoperation including: stopping, before voltages of all the plurality ofcells reach 0 V, the second discharge operation.
 9. The storage batterypack according to claim 1, wherein the controller performs the firstdischarge operation under a condition that (i) the storage battery packis connected to a charging device, (ii) the voltage of the secondarybattery is lower than a second threshold value which is higher than thefirst threshold value, and (iii) a predetermined period has elapsedsince a last first discharge which has been performed.
 10. The storagebattery pack according to claim 1, further comprises: a communicatorthat allows communication with an external entity, wherein, the memoryincluding a set of executable instructions that, when executed by thecontroller, causes the controller to perform operations including:transmitting state information indicating a remaining capacity of thesecondary battery to the external entity via the communicator.
 11. Thestorage battery pack according to claim 1, further comprises: acommunicator that allows communication with an external entity, wherein,the memory including a set of executable instructions that, whenexecuted by the controller, causes the controller to perform operationsincluding: receiving information, via the communicator, indicatingcommand for causing the storage battery pack to check a remainingcapacity of the storage battery pack from the external entity, andtransmitting, in response for the command, state information indicatingthe remaining capacity of the secondary battery to the external entityvia the communicator.
 12. The storage battery pack according to claim 1,wherein, the memory including a set of executable instructions that,when executed by the controller, causes the controller to performoperations including: detecting a signal indicating a start of charge,the controller performs, when the signal indicating the start of chargeis detected, the first discharge operation under a condition that (i)the storage battery pack is connected to a charging device, and (ii) thevoltage of the secondary battery is lower than a second threshold valuewhich is higher than the first threshold value.
 13. The storage batterypack according to claim 1, wherein, the memory including a set ofexecutable instructions that, when executed by the controller, causesthe controller to perform operations including: receiving information,via the communicator, indicating command for causing the storage batterypack to perform the second discharge operation from the external entity,and performing, in response for the command, the second dischargeoperation.
 14. A battery management method for controlling a storagebattery pack including a secondary battery, the battery managementmethod comprising: performing a first discharge operation under acondition that: (i) the storage battery pack is connected to a chargingdevice; (ii) a voltage of the secondary battery is higher than a firstthreshold value which is higher than a discharge cutoff voltage of thesecondary battery; and (iii) the voltage of the secondary battery islower than a second threshold value which is higher than the firstthreshold value, wherein, the first discharge operation including:consuming a remaining power of the secondary battery until the voltageof the secondary battery reaches the first threshold value; andstopping, when the voltage of the secondary battery reaches the firstthreshold value, the first discharge operation, performing a seconddischarge operation under a condition that: the storage battery pack hasbeen received, from an external entity, a command for causing thestorage battery pack to perform the second discharge operation, wherein,the second discharge operation including: consuming the remaining powerof the secondary battery until the voltage of the secondary batteryreaches a third threshold value which is lower than the discharge cutoffvoltage.
 15. The battery management method according to claim 14,further comprising: transmitting state information indicating aremaining capacity of the secondary battery to the external entity via acommunicator of the storage battery pack.
 16. The battery managementmethod according to claim 15, further comprising: displaying, on adisplay of the external entity, a remaining capacity of the secondarybattery based on the state information.
 17. The battery managementmethod according to claim 14, further comprising: receiving information,via a communicator of the storage battery pack, indicating the commandfor causing the storage battery pack to perform the second dischargeoperation from the external entity.